Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
Buzz Aldrin says US must colonize Mars
28 views
Skip to first unread message
dump...@hotmail.com
May 9, 2013, 1:05:54 PM5/9/13
to
"Buzz Aldrin, the American astronaut who
was the second man to walk on the Moon,
said Wednesday that the United States
must lead the way toward building a
permanent settlement on Mars."
See:
http://www.marsdaily.com/reports/Buzz_Aldrin_says_US_must_colonize_Mars_999.html
was the second man to walk on the Moon,
said Wednesday that the United States
must lead the way toward building a
permanent settlement on Mars."
See:
http://www.marsdaily.com/reports/Buzz_Aldrin_says_US_must_colonize_Mars_999.html
bob haller
May 9, 2013, 8:38:46 PM5/9/13
to
niel should be the one pushing mars immediately after he got back from
the moon......
armstrong was a wonderful pilot but a total zip to lead future
exploration.....
Greg (Strider) Moore
May 10, 2013, 5:17:23 AM5/10/13
to
"bob haller" wrote in message
news:8a7cdd12-92b4-4b81...@l5g2000vbn.googlegroups.com...
Guess what. He was hired for his piloting abilities, not his marketing or
political abilities.
He did what he was hired to do.
>
>
--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
news:8a7cdd12-92b4-4b81...@l5g2000vbn.googlegroups.com...
political abilities.
He did what he was hired to do.
>
>
--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
bob haller
May 10, 2013, 7:51:13 AM5/10/13
to
On May 10, 5:17 am, "Greg \(Strider\) Moore"
guess what he was the first man to step on the moon.:)
As such his destiny should of included helping to rally for a mars
mission.:)
I am certain he was choosen to e lowkey about all the hoopla after the
landing but he voluntarily fded from site.....
As such his destiny should of included helping to rally for a mars
mission.:)
I am certain he was choosen to e lowkey about all the hoopla after the
landing but he voluntarily fded from site.....
Hg
May 10, 2013, 8:04:55 AM5/10/13
to
Mars mission and that was all fine and dandy, though I wonder were
they really serious about it? Assuming that they were given money
from the government to carry out a manned Mars mission in the 70's,
did they really have enough knowledge of the dangers of travel to
Mars to negate risk to life?
Reason why I'm asking is even with our current technology today we
can't fully protect humans from the dangers of interplanetary travel.
IMHO attempting a mission with 70's technology would likely result in
fatalities (probably the entire crew.)
--
T
bob haller
May 10, 2013, 9:54:50 AM5/10/13
to
Message has been deleted
Quadibloc
May 10, 2013, 4:38:48 PM5/10/13
to
On May 10, 9:02 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> What great advances in rocketry and aerospace do you
> think there have been since then that are critical to such a mission?
A mission to Mars requires spending tax dollars, as it would be very
expensive. And no particularly compelling reason exists to carry out
such a mission - unlike the need to invigorate the credibility of the
United States for Cold War purposes in the 1960s.
So the political will isn't there. If China - or North Korea - lands
astronauts on the Moon, this would likely change.
Right now, it's also very unclear that a trip to Mars, as it would
take over a year, rather than a few days, could be carried out with a
reasonable degree of safety. The level of radiation exposure could
well be enough to make such a mission reckless. Life support for such
a mission also has not yet been developed.
Those aren't insuperable problems - they're natural consequences of
doing anything for the first time. If you could buy a plane ticket to
Mars, someone else would have to have been there first. It isn't
impossible, but it will be a challenge. And right now, most people
simply don't see a good reason to bother. I don't know how to change
that.
John Savard
> What great advances in rocketry and aerospace do you
> think there have been since then that are critical to such a mission?
A mission to Mars requires spending tax dollars, as it would be very
expensive. And no particularly compelling reason exists to carry out
such a mission - unlike the need to invigorate the credibility of the
United States for Cold War purposes in the 1960s.
So the political will isn't there. If China - or North Korea - lands
astronauts on the Moon, this would likely change.
Right now, it's also very unclear that a trip to Mars, as it would
take over a year, rather than a few days, could be carried out with a
reasonable degree of safety. The level of radiation exposure could
well be enough to make such a mission reckless. Life support for such
a mission also has not yet been developed.
Those aren't insuperable problems - they're natural consequences of
doing anything for the first time. If you could buy a plane ticket to
Mars, someone else would have to have been there first. It isn't
impossible, but it will be a challenge. And right now, most people
simply don't see a good reason to bother. I don't know how to change
that.
John Savard
Message has been deleted
bob haller
May 10, 2013, 11:13:29 PM5/10/13
to
>
> >Right now, it's also very unclear that a trip to Mars, as it would
>
> Uh, around 6 months each way.
>
a fraction of that with nuke power booster for travel between
planets.....
trip would be near 3 years if you want more than fag and
footprints.....
plus a big nuclear booster transporting a failrly small cargo
container of critical supplies would increase the safety factor
Hg
May 11, 2013, 1:16:28 AM5/11/13
to
at. Solar flares, Charged particles,Cosmic Rays etc are a major worry
in any expedition to Mars. Though work is slowly being down to lessen
these dangers I have yet to read about any definitive method of
protecting people on their way to Mars.
What do I know though? Not much. Though I remember a guy who's been in
space for more than a year in total, Michael Foale, saying back in 2000
that he would not think about a Mars mission until he was considerably
older, possibly even nearing retirement age as he was just too scared
about radiation exposure and developing cancer so he would not go
until he reached an age where cancer may be likely to develop - and
obviously he wanted to enjoy life without worrying about putting his
body through a situation that would lessen his life expectancy.
--
T
Hg
May 11, 2013, 1:20:27 AM5/11/13
to
Doh! Of course I meant slowly being done.
--
T
bob haller
May 11, 2013, 8:42:15 AM5/11/13
to
shielded with water all around the living area ahead of a crewed
attempt.
the heavily shielded would leave earth unmanned but with lots of
sensors sending back info. the crew module would orbit mars and act as
a lifeboat if something goes wrong.
be in place unmanned waiting for the actual first crewed visit...
Message has been deleted
Message has been deleted
bob haller
May 11, 2013, 3:54:14 PM5/11/13
to
On May 11, 11:36 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> alternative is to simply surround the crew compartment with water. The
> reason you don't see big splashy headlines about solutions is because
> these aren't difficult problems.
>
> --
> "The reasonable man adapts himself to the world; the unreasonable
> man persists in trying to adapt the world to himself. Therefore,
> all progress depends on the unreasonable man."
> --George Bernard Shaw
Not difficult?
Perhaps solvable, but difficult they will be........
Lack of gravity, vision problems, having enough supplies and
equiptement to repair or overcome any and all problems on what will
likely be a multi year trip.....
> Hg <H...@Hg.Hg> wrote:
> >On 11/05/2013 01:38, Quadibloc wrote:
> >> On May 10, 9:02 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> >>> What great advances in rocketry and aerospace do you
> >>> think there have been since then that are critical to such a mission?
>
> >> A mission to Mars requires spending tax dollars, as it would be very
> >> expensive. And no particularly compelling reason exists to carry out
> >> such a mission - unlike the need to invigorate the credibility of the
> >> United States for Cold War purposes in the 1960s.
>
> >> So the political will isn't there. If China - or North Korea - lands
> >> astronauts on the Moon, this would likely change.
>
> >> Right now, it's also very unclear that a trip to Mars, as it would
> >> take over a year, rather than a few days, could be carried out with a
> >> reasonable degree of safety. The level of radiation exposure could
> >> well be enough to make such a mission reckless. Life support for such
> >> a mission also has not yet been developed.
>
> >> Those aren't insuperable problems - they're natural consequences of
> >> doing anything for the first time. If you could buy a plane ticket to
> >> Mars, someone else would have to have been there first. It isn't
> >> impossible, but it will be a challenge. And right now, most people
> >> simply don't see a good reason to bother. I don't know how to change
> >> that.
>
> >On 11/05/2013 01:38, Quadibloc wrote:
> >> On May 10, 9:02 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> >>> What great advances in rocketry and aerospace do you
> >>> think there have been since then that are critical to such a mission?
>
> >> A mission to Mars requires spending tax dollars, as it would be very
> >> expensive. And no particularly compelling reason exists to carry out
> >> such a mission - unlike the need to invigorate the credibility of the
> >> United States for Cold War purposes in the 1960s.
>
> >> So the political will isn't there. If China - or North Korea - lands
> >> astronauts on the Moon, this would likely change.
>
> >> Right now, it's also very unclear that a trip to Mars, as it would
> >> take over a year, rather than a few days, could be carried out with a
> >> reasonable degree of safety. The level of radiation exposure could
> >> well be enough to make such a mission reckless. Life support for such
> >> a mission also has not yet been developed.
>
> >> Those aren't insuperable problems - they're natural consequences of
> >> doing anything for the first time. If you could buy a plane ticket to
> >> Mars, someone else would have to have been there first. It isn't
> >> impossible, but it will be a challenge. And right now, most people
> >> simply don't see a good reason to bother. I don't know how to change
> >> that.
>
> >This is the only reply to my post that understands what I was getting
> >at. Solar flares, Charged particles,Cosmic Rays etc are a major worry
> >in any expedition to Mars. Though work is slowly being down to lessen
> >these dangers I have yet to read about any definitive method of
> >protecting people on their way to Mars.
>
> Look it up. It's not all that difficult to do. The simplest
> >at. Solar flares, Charged particles,Cosmic Rays etc are a major worry
> >in any expedition to Mars. Though work is slowly being down to lessen
> >these dangers I have yet to read about any definitive method of
> >protecting people on their way to Mars.
>
> alternative is to simply surround the crew compartment with water. The
> reason you don't see big splashy headlines about solutions is because
> these aren't difficult problems.
>
> --
> "The reasonable man adapts himself to the world; the unreasonable
> man persists in trying to adapt the world to himself. Therefore,
> all progress depends on the unreasonable man."
> --George Bernard Shaw
Not difficult?
Perhaps solvable, but difficult they will be........
Lack of gravity, vision problems, having enough supplies and
equiptement to repair or overcome any and all problems on what will
likely be a multi year trip.....
Message has been deleted
bob haller
May 11, 2013, 7:11:42 PM5/11/13
to
On May 11, 6:10 pm, Fred J. McCall <fjmcc...@gmail.com> wrote:
>
> Right. Not difficult.
> you're being disingenuous in referring to "a multi-year trip" since
> you know the trip time is around 6 months each way.
>
> However, let's look at a few of those, shall we? Lack of gravity?
> Spin on a tether. Vision problems? Presumably either the result of
> sustained zero-g (spin on a tether) or radiation (water shielding).
> Supplies and equipment is done the same way you handle a trip across
> town.
>
> Again, these are NOT technically difficult problems.
>
> --
> "Some people get lost in thought because it's such unfamiliar
> territory."
> --G. Behn
do we really need a quick flag and footprints mission?
were going to spend half a trillion bucks to have a crew on mars for a
week?
No one has ever tested for long term a tether spin
supplies both food water and spares is much harder than going across
town..........
Taking every single item you might need including anything that could
break down for a year?
A nuclear booster could cut travel time to a 2.5 months each way
allowing a decent amount of ground time while cutting the amount of
everything going to mars....
> bob haller <hall...@aol.com> wrote:
> >On May 11, 11:36 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> >> Hg <H...@Hg.Hg> wrote:
>
> >> >This is the only reply to my post that understands what I was getting
> >> >at. Solar flares, Charged particles,Cosmic Rays etc are a major worry
> >> >in any expedition to Mars. Though work is slowly being down to lessen
> >> >these dangers I have yet to read about any definitive method of
> >> >protecting people on their way to Mars.
>
> >> Look it up. It's not all that difficult to do. The simplest
> >> alternative is to simply surround the crew compartment with water. The
> >> reason you don't see big splashy headlines about solutions is because
> >> these aren't difficult problems.
>
> >Not difficult?
> >On May 11, 11:36 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> >> Hg <H...@Hg.Hg> wrote:
>
> >> >This is the only reply to my post that understands what I was getting
> >> >at. Solar flares, Charged particles,Cosmic Rays etc are a major worry
> >> >in any expedition to Mars. Though work is slowly being down to lessen
> >> >these dangers I have yet to read about any definitive method of
> >> >protecting people on their way to Mars.
>
> >> Look it up. It's not all that difficult to do. The simplest
> >> alternative is to simply surround the crew compartment with water. The
> >> reason you don't see big splashy headlines about solutions is because
> >> these aren't difficult problems.
>
>
> Right. Not difficult.
>
>
>
> >Perhaps solvable, but difficult they will be........
>
> For you, perhaps.
>
>
> >Perhaps solvable, but difficult they will be........
>
>
>
>
> >Lack of gravity, vision problems, having enough supplies and
> >equiptement to repair or overcome any and all problems on what will
> >likely be a multi year trip.....
>
> Note that none of the preceding are what was being discussed and
>
>
> >Lack of gravity, vision problems, having enough supplies and
> >equiptement to repair or overcome any and all problems on what will
> >likely be a multi year trip.....
>
> you're being disingenuous in referring to "a multi-year trip" since
> you know the trip time is around 6 months each way.
>
> However, let's look at a few of those, shall we? Lack of gravity?
> Spin on a tether. Vision problems? Presumably either the result of
> sustained zero-g (spin on a tether) or radiation (water shielding).
> Supplies and equipment is done the same way you handle a trip across
> town.
>
> Again, these are NOT technically difficult problems.
>
> --
> "Some people get lost in thought because it's such unfamiliar
> territory."
> --G. Behn
do we really need a quick flag and footprints mission?
were going to spend half a trillion bucks to have a crew on mars for a
week?
No one has ever tested for long term a tether spin
supplies both food water and spares is much harder than going across
town..........
Taking every single item you might need including anything that could
break down for a year?
A nuclear booster could cut travel time to a 2.5 months each way
allowing a decent amount of ground time while cutting the amount of
everything going to mars....
jacob navia
May 11, 2013, 7:25:18 PM5/11/13
to
Le 12/05/13 00:10, Fred J. McCall a �crit :
>>
>> Lack of gravity, vision problems, having enough supplies and
>> equiptement to repair or overcome any and all problems on what will
>> likely be a multi year trip.....
>>
>
Lack of gravity: the solution you propose has never been built. You need
a much larger spaceship to do the spin. Add mass to the ship.
Water shielding: Not complicated but again, this has never been done.
What about the problem of water getting radioactive because of the
radiation it absorbs? In all cases you must add several hundred tons
at least to the ship's mass. Yes, you do not need to shield all the
ship but the crew quarters must be shielded and they MUST be bigger than
a small appartement to avoid people getting crazy in the years they must
live inside.
Supplies and equipment is done the same way you handle a trip across
town you say...
That is completely nonsense. All the equipment MUST run perfectly
for 2 years at least. This *is* a multi year trip. It takes 6 months to
get to Mars, but then you have to wait for 2 years for the next
opportunity to come back!
So, count 3 years AT LEAST. Any failure to the equipment in that time
frame is fatal.
Yes redundancy is possible but... Add more mass to the ship!
A mars trip will be possible when our technology advances with new
materials that are light and can shield a spaceship or with new
methods for shielding using powerful electrical fields, etc.
We need to develop a space ecology (plants, etc) to avoid carrying tons
of food and oxygen for 3 years! The technology to develop that is
*probably* there (genetics, cultivation in space) but never tested!
A trip to Mars is right now beyond our reach.
Anyway all this is nonsense. The U.S. isn't able to go to the moon,
(a trip of a few days) so speaking about Mars (a trip of a few years)
is day dreaming.
>>
>> Lack of gravity, vision problems, having enough supplies and
>> equiptement to repair or overcome any and all problems on what will
>> likely be a multi year trip.....
>>
>
> Note that none of the preceding are what was being discussed and
> you're being disingenuous in referring to "a multi-year trip" since
> you know the trip time is around 6 months each way.
>
> However, let's look at a few of those, shall we? Lack of gravity?
> Spin on a tether. Vision problems? Presumably either the result of
> sustained zero-g (spin on a tether) or radiation (water shielding).
> Supplies and equipment is done the same way you handle a trip across
> town.
>
> Again, these are NOT technically difficult problems.
>
What?
> you're being disingenuous in referring to "a multi-year trip" since
> you know the trip time is around 6 months each way.
>
> However, let's look at a few of those, shall we? Lack of gravity?
> Spin on a tether. Vision problems? Presumably either the result of
> sustained zero-g (spin on a tether) or radiation (water shielding).
> Supplies and equipment is done the same way you handle a trip across
> town.
>
> Again, these are NOT technically difficult problems.
>
Lack of gravity: the solution you propose has never been built. You need
a much larger spaceship to do the spin. Add mass to the ship.
Water shielding: Not complicated but again, this has never been done.
What about the problem of water getting radioactive because of the
radiation it absorbs? In all cases you must add several hundred tons
at least to the ship's mass. Yes, you do not need to shield all the
ship but the crew quarters must be shielded and they MUST be bigger than
a small appartement to avoid people getting crazy in the years they must
live inside.
Supplies and equipment is done the same way you handle a trip across
That is completely nonsense. All the equipment MUST run perfectly
for 2 years at least. This *is* a multi year trip. It takes 6 months to
get to Mars, but then you have to wait for 2 years for the next
opportunity to come back!
So, count 3 years AT LEAST. Any failure to the equipment in that time
frame is fatal.
Yes redundancy is possible but... Add more mass to the ship!
A mars trip will be possible when our technology advances with new
materials that are light and can shield a spaceship or with new
methods for shielding using powerful electrical fields, etc.
We need to develop a space ecology (plants, etc) to avoid carrying tons
of food and oxygen for 3 years! The technology to develop that is
*probably* there (genetics, cultivation in space) but never tested!
A trip to Mars is right now beyond our reach.
Anyway all this is nonsense. The U.S. isn't able to go to the moon,
(a trip of a few days) so speaking about Mars (a trip of a few years)
is day dreaming.
Message has been deleted
Message has been deleted
bob haller
May 12, 2013, 9:22:50 AM5/12/13
to
On May 11, 7:52 pm, Fred J. McCall <fjmcc...@gmail.com> wrote:
> the overall mission mass. The spaceship is the same size it would
> have been without the tether.
> use fuel oil, but it's the same principle.
> long-term space habitat.
> above, we'd still be living in caves and eating berries (except nobody
> has ever eaten those berries to test for long term effects, so we'd
> have to avoid those, too) and puzzling about whether fire was
> sufficiently safe.
> all this stuff. READ ONE!
> possible at whatever point in time those things are developed.
> for trips of this length.
> But that's what you really want anyway, isn't it?
>
> Enjoy that cave. Hope you decide there's been sufficient study of the
> long term effects of those berries before you starve to death.
>
> Meanwhile, those of us who actually own a working set of testicles
> will continue to look at and plan for the future.
>
> --
> "Insisting on perfect safety is for people who don't have the balls to
> live in the real world."
> -- Mary Shafer, NASA Dryden
fred your saying its so means nothing.... unless your volunteering to
be on the first trip. If your hide is on the line you may be more
concerned about safety...
Besides we dont know what we dont know.....
Oh and Fred the poster you were responding to is not ME. and I only
use one name:)
Its sad we tossed out the apollo capabilties to fund the shuttle to
just go round and round....
while ignoring nuclear boosters, and heavy lift, and everything else
to really go explore.....
> jacob navia <ja...@spamsink.net> wrote:
> >Le 12/05/13 00:10, Fred J. McCall a crit :
>
> >>> Lack of gravity, vision problems, having enough supplies and
> >>> equiptement to repair or overcome any and all problems on what will
> >>> likely be a multi year trip.....
>
> >> Note that none of the preceding are what was being discussed and
> >> you're being disingenuous in referring to "a multi-year trip" since
> >> you know the trip time is around 6 months each way.
>
> >> However, let's look at a few of those, shall we? Lack of gravity?
> >> Spin on a tether. Vision problems? Presumably either the result of
> >> sustained zero-g (spin on a tether) or radiation (water shielding).
> >> Supplies and equipment is done the same way you handle a trip across
> >> town.
>
> >> Again, these are NOT technically difficult problems.
>
> >What?
>
> Are you stupid? It's fairly simple English.
> >Le 12/05/13 00:10, Fred J. McCall a crit :
>
> >>> Lack of gravity, vision problems, having enough supplies and
> >>> equiptement to repair or overcome any and all problems on what will
> >>> likely be a multi year trip.....
>
> >> Note that none of the preceding are what was being discussed and
> >> you're being disingenuous in referring to "a multi-year trip" since
> >> you know the trip time is around 6 months each way.
>
> >> However, let's look at a few of those, shall we? Lack of gravity?
> >> Spin on a tether. Vision problems? Presumably either the result of
> >> sustained zero-g (spin on a tether) or radiation (water shielding).
> >> Supplies and equipment is done the same way you handle a trip across
> >> town.
>
> >> Again, these are NOT technically difficult problems.
>
> >What?
>
>
>
>
> >Lack of gravity: the solution you propose has never been built. You need
> >a much larger spaceship to do the spin. Add mass to the ship.
>
> Nonsense. A tether adds practically no weight at all when you look at
>
>
> >Lack of gravity: the solution you propose has never been built. You need
> >a much larger spaceship to do the spin. Add mass to the ship.
>
> the overall mission mass. The spaceship is the same size it would
> have been without the tether.
>
>
>
> >Water shielding: Not complicated but again, this has never been done.
>
> Of course it has. Look at the layout of a nuclear sub sometime. They
>
>
> >Water shielding: Not complicated but again, this has never been done.
>
> use fuel oil, but it's the same principle.
>
>
>
> >What about the problem of water getting radioactive because of the
> >radiation it absorbs?
>
> It's not really a problem.
>
>
> >What about the problem of water getting radioactive because of the
> >radiation it absorbs?
>
>
>
>
> >In all cases you must add several hundred tons
> >at least to the ship's mass.
>
> You need the water anyway. It actually adds very little to overall
>
>
> >In all cases you must add several hundred tons
> >at least to the ship's mass.
>
> mass.
>
>
>
> >Yes, you do not need to shield all the
> >ship but the crew quarters must be shielded and they MUST be bigger than
> >a small appartement to avoid people getting crazy in the years they must
> >live inside.
>
> You might want to actually take a look at the size of the typical
>
>
>
> >Yes, you do not need to shield all the
> >ship but the crew quarters must be shielded and they MUST be bigger than
> >a small appartement to avoid people getting crazy in the years they must
> >live inside.
>
> long-term space habitat.
>
>
>
> >Supplies and equipment is done the same way you handle a trip across
> >town you say...
>
> >That is completely nonsense. All the equipment MUST run perfectly
> >for 2 years at least. This *is* a multi year trip. It takes 6 months to
> >get to Mars, but then you have to wait for 2 years for the next
> >opportunity to come back!
>
> Hogwash. You just carry some spares. Given your sort of reasoning,
>
>
> >Supplies and equipment is done the same way you handle a trip across
> >town you say...
>
> >That is completely nonsense. All the equipment MUST run perfectly
> >for 2 years at least. This *is* a multi year trip. It takes 6 months to
> >get to Mars, but then you have to wait for 2 years for the next
> >opportunity to come back!
>
> above, we'd still be living in caves and eating berries (except nobody
> has ever eaten those berries to test for long term effects, so we'd
> have to avoid those, too) and puzzling about whether fire was
> sufficiently safe.
>
>
>
> >So, count 3 years AT LEAST. Any failure to the equipment in that time
> >frame is fatal.
>
> Off by a year. You've been told this before. PAY ATTENTION!
>
>
> >So, count 3 years AT LEAST. Any failure to the equipment in that time
> >frame is fatal.
>
>
>
>
> >Yes redundancy is possible but... Add more mass to the ship!
>
> You know, people have done detailed studies of the mass budgets for
>
>
> >Yes redundancy is possible but... Add more mass to the ship!
>
> all this stuff. READ ONE!
>
>
>
> >A mars trip will be possible when our technology advances with new
> >materials that are light and can shield a spaceship or with new
> >methods for shielding using powerful electrical fields, etc.
>
> Since a Mars trip is possible now, presumably it would also be
>
>
> >A mars trip will be possible when our technology advances with new
> >materials that are light and can shield a spaceship or with new
> >methods for shielding using powerful electrical fields, etc.
>
> possible at whatever point in time those things are developed.
>
>
>
> >We need to develop a space ecology (plants, etc) to avoid carrying tons
> >of food and oxygen for 3 years! The technology to develop that is
> >*probably* there (genetics, cultivation in space) but never tested!
>
> It's actually simpler and cheaper to just carry everything with you
>
>
> >We need to develop a space ecology (plants, etc) to avoid carrying tons
> >of food and oxygen for 3 years! The technology to develop that is
> >*probably* there (genetics, cultivation in space) but never tested!
>
> for trips of this length.
>
>
>
> >A trip to Mars is right now beyond our reach.
>
> Hogwash.
>
>
> >A trip to Mars is right now beyond our reach.
>
>
>
>
> >Anyway all this is nonsense. The U.S. isn't able to go to the moon,
> >(a trip of a few days) so speaking about Mars (a trip of a few years)
> >is day dreaming.
>
> If you never talk about how to do it, you'll never be able to do it.
>
>
> >Anyway all this is nonsense. The U.S. isn't able to go to the moon,
> >(a trip of a few days) so speaking about Mars (a trip of a few years)
> >is day dreaming.
>
> But that's what you really want anyway, isn't it?
>
> Enjoy that cave. Hope you decide there's been sufficient study of the
> long term effects of those berries before you starve to death.
>
> Meanwhile, those of us who actually own a working set of testicles
> will continue to look at and plan for the future.
>
> --
> "Insisting on perfect safety is for people who don't have the balls to
> live in the real world."
> -- Mary Shafer, NASA Dryden
fred your saying its so means nothing.... unless your volunteering to
be on the first trip. If your hide is on the line you may be more
concerned about safety...
Besides we dont know what we dont know.....
Oh and Fred the poster you were responding to is not ME. and I only
use one name:)
Its sad we tossed out the apollo capabilties to fund the shuttle to
just go round and round....
while ignoring nuclear boosters, and heavy lift, and everything else
to really go explore.....
Message has been deleted
jacob navia
May 12, 2013, 5:25:33 PM5/12/13
to
Le 12/05/13 00:10, Fred J. McCall a �crit :
Reality is a little bit more complicated.
Vibrations
Computer models frequently show tethers can snap due to vibration.
Mechanical tether-handling equipment is often surprisingly heavy, with
complex controls to damp vibrations.
The vibration modes that may be a problem include skipping rope,
transverse, longitudinal, and pendulum.[25]
Tethers are nearly always tapered, and this can greatly amplify the
movement at the thinnest tip in whip like ways.
http://en.wikipedia.org/wiki/Space_tether
Another problem is pointed out by the site listed below:
The problem is, space tethers are a formidable engineering challenge.
They need to be thin, light and flexible in order to fit inside of a
spacecraft or launch vehicle, they need to be extremely long, they need
to be strong enough to support a payload as well as their own weight,
and, if they must transmit power or data, they need to maintain internal
integrity. In other words, it doesn't help if the tether doesn�t break
if the electric wire inside snaps. At the moment, experimental tethers
haven�t had a great track record. About half fail to deploy, snap or are
broken by micrometeoroids.
http://www.gizmag.com/esa-space-tether/26879/
All mankind experience with tethers are very small ones used in
satellites/light payloads. Building one to simulate gravity in a long
term space mission is an ENORMOUS engineering challenge for which
we have NO IDEA of the difficulties since it has never been done!
It would take several YEARS of effort and years of testing to figure out
a tether configuration that is stable enough to trust the life of a
crew for 2+ years!
What happens if the tethers snap?
Well the two pieces of the spacecraft start traveling each on its own
directon. Since the spaceship is cut in half, the total loss of the
people inside is certain. That would be then a CRITICAL piece of the
space craft that MUST hold for 2+ years.
Sure it can be done, but I do not see any easy way of doing that.
A Mars mission will come AFTER a moon colony is established, and mankind
acquires experience with deep space missions, develops the materials,
procedures, and environments where missions of several years can be
designed and executed.
Just crying "Let's go to Mars" is ridiculous. The only way is to build
experience in the moon, that is only a few days away from here.
> Lack of gravity?
> Spin on a tether.
Yes. Very easy said.
> Spin on a tether.
Reality is a little bit more complicated.
Vibrations
Computer models frequently show tethers can snap due to vibration.
Mechanical tether-handling equipment is often surprisingly heavy, with
complex controls to damp vibrations.
The vibration modes that may be a problem include skipping rope,
transverse, longitudinal, and pendulum.[25]
Tethers are nearly always tapered, and this can greatly amplify the
movement at the thinnest tip in whip like ways.
http://en.wikipedia.org/wiki/Space_tether
Another problem is pointed out by the site listed below:
The problem is, space tethers are a formidable engineering challenge.
They need to be thin, light and flexible in order to fit inside of a
spacecraft or launch vehicle, they need to be extremely long, they need
to be strong enough to support a payload as well as their own weight,
and, if they must transmit power or data, they need to maintain internal
integrity. In other words, it doesn't help if the tether doesn�t break
if the electric wire inside snaps. At the moment, experimental tethers
haven�t had a great track record. About half fail to deploy, snap or are
broken by micrometeoroids.
http://www.gizmag.com/esa-space-tether/26879/
All mankind experience with tethers are very small ones used in
satellites/light payloads. Building one to simulate gravity in a long
term space mission is an ENORMOUS engineering challenge for which
we have NO IDEA of the difficulties since it has never been done!
It would take several YEARS of effort and years of testing to figure out
a tether configuration that is stable enough to trust the life of a
crew for 2+ years!
What happens if the tethers snap?
Well the two pieces of the spacecraft start traveling each on its own
directon. Since the spaceship is cut in half, the total loss of the
people inside is certain. That would be then a CRITICAL piece of the
space craft that MUST hold for 2+ years.
Sure it can be done, but I do not see any easy way of doing that.
A Mars mission will come AFTER a moon colony is established, and mankind
acquires experience with deep space missions, develops the materials,
procedures, and environments where missions of several years can be
designed and executed.
Just crying "Let's go to Mars" is ridiculous. The only way is to build
experience in the moon, that is only a few days away from here.
Message has been deleted
bob haller
May 12, 2013, 7:24:22 PM5/12/13
to
> I'd be more than happy to volunteer for that first trip on a properly
> designed mission if they'd let me.
Do you believe the doctors at the mental, hospital you live in would
clear you to go to mars???
>
> Meanwhile, I guess the reason you work out of your house is that
> you're afraid of the drive to work?
>
Far from it, doing field service all over the pittsburgh area I drive
about 40,000 miles a year, although with the costs of gas I have tried
to save miles when I can
Message has been deleted
bob haller
May 13, 2013, 12:12:45 AM5/13/13
to
>
> However do you bring yourself to do that, since it's impossible for
> you to carry along everything you could possibly need that might go
> wrong with your car and you cannot carry sufficient supplies for the
> trip?
Thats what AAA tow truck is for:) plus theres little risk of dying if
my vehicle breaks down.....
Message has been deleted
bob haller
May 13, 2013, 5:42:27 AM5/13/13
to
On May 13, 2:27 am, Fred J. McCall <fjmcc...@gmail.com> wrote:
> wrong, no matter how unlikely, with you. Think about that.
> likelihood of you dying than of someone on an orbital trajectory
> dying.
mars with no chance of resupply en route you MUST carry everything
with you.......
> bob haller <hall...@aol.com> wrote:
>
> >> However do you bring yourself to do that, since it's impossible for
> >> you to carry along everything you could possibly need that might go
> >> wrong with your car and you cannot carry sufficient supplies for the
> >> trip?
>
> >Thats what AAA tow truck is for:)
>
> Oh, so you don't HAVE to carry everything that might possibly go
>
> >> However do you bring yourself to do that, since it's impossible for
> >> you to carry along everything you could possibly need that might go
> >> wrong with your car and you cannot carry sufficient supplies for the
> >> trip?
>
> >Thats what AAA tow truck is for:)
>
> wrong, no matter how unlikely, with you. Think about that.
>
>
>
> >plus theres little risk of dying if
> >my vehicle breaks down.....
>
> Of course there is. Unfriendly natives, you know. Much more
>
>
> >plus theres little risk of dying if
> >my vehicle breaks down.....
>
> likelihood of you dying than of someone on an orbital trajectory
> dying.
>
> --
> "Some people get lost in thought because it's such unfamiliar
> territory."
> --G. Behn
fred you are truly a loon if you cant understand that on a trip to
> --
> "Some people get lost in thought because it's such unfamiliar
> territory."
> --G. Behn
mars with no chance of resupply en route you MUST carry everything
with you.......
jacob navia
May 13, 2013, 8:00:46 AM5/13/13
to
Le 13/05/13 00:28, Fred J. McCall a �crit :
> And just how does "experience in the moon" translate to either 6 month
> long deep space flights OR spending time on Mars?
In no particular order:
1) Experience in space-suits design/reliability
2) Experience in building reliable components that work for longer
periods of time in deep space conditions. What materials become
brittle after 2 years in deep space? How do computer systems
resist? How about the water recycling machines, the CO2 extracting
machines, etc?
3) Experience in deep space radiation hardening, effects of deep space
radiation in living beings.
4) Experience in developing autonomous "gardens" to provide for oxygen
recycling and food for very long missions. The objective is to
acquire know how to be able to fly 2 years producing food aboard
instead of shipping everything from earth and forcing the crew to
survive in canned food for years.
5) Experience in building habitats for humans underground in another
planet. Experience with testing building materials, machines that
work at a percentage of gravity of the earth in deep space,
resistance of the materials to radiation, etc.
And this list is by no means exhaustive.
NOTE: Mars approaches Earth once every TWO earth years. The mission
must be designed for at least 2 years.
NOTE: I am speaking about DEEP space, not the space station
environment that is still shielded from radiation by earth's
magnetic field.
> And just how does "experience in the moon" translate to either 6 month
> long deep space flights OR spending time on Mars?
In no particular order:
1) Experience in space-suits design/reliability
2) Experience in building reliable components that work for longer
periods of time in deep space conditions. What materials become
brittle after 2 years in deep space? How do computer systems
resist? How about the water recycling machines, the CO2 extracting
machines, etc?
3) Experience in deep space radiation hardening, effects of deep space
radiation in living beings.
4) Experience in developing autonomous "gardens" to provide for oxygen
recycling and food for very long missions. The objective is to
acquire know how to be able to fly 2 years producing food aboard
instead of shipping everything from earth and forcing the crew to
survive in canned food for years.
5) Experience in building habitats for humans underground in another
planet. Experience with testing building materials, machines that
work at a percentage of gravity of the earth in deep space,
resistance of the materials to radiation, etc.
And this list is by no means exhaustive.
NOTE: Mars approaches Earth once every TWO earth years. The mission
must be designed for at least 2 years.
NOTE: I am speaking about DEEP space, not the space station
environment that is still shielded from radiation by earth's
magnetic field.
jacob navia
May 13, 2013, 8:06:40 AM5/13/13
to
Le 13/05/13 00:28, Fred J. McCall a écrit :
> That's because you're just a bit of a thickie.
Unable to argue with any facts, Mr McCall just throws insults, as usual.
I just took ONE proposal out of his hogwash and investigated it for 1
hour. That time suffices to discover how hollow his assertions are.
"Build a tether".
Of course. Very easy.
"How do I go from Paris to New York"?
Mr McCall:
"Learn to swimm and build a canoe"
> That's because you're just a bit of a thickie.
Unable to argue with any facts, Mr McCall just throws insults, as usual.
I just took ONE proposal out of his hogwash and investigated it for 1
hour. That time suffices to discover how hollow his assertions are.
"Build a tether".
Of course. Very easy.
"How do I go from Paris to New York"?
Mr McCall:
"Learn to swimm and build a canoe"
Jeff Findley
May 13, 2013, 9:28:24 AM5/13/13
to
In article <kmqklb$8de$1...@speranza.aioe.org>, ja...@spamsink.net says...
>
> Le 13/05/13 00:28, Fred J. McCall a ï¿œcrit :
a. Cooling needs to be completely different since even the thin Mars
atmosphere prevents using water/ice sublimation for cooling (like is
done on the moon).
b. Lunar dust is extremely abrasive due to lack of wind (which is
present on Mars). So, solving the lunar dust abrasion problem is
"overkill" for Mars.
c. Mars gravity is much higher than the moon, so suits that work well
on the moon (e.g. Apollo suits) are far too heavy for Mars.
> 2) Experience in building reliable components that work for longer
> periods of time in deep space conditions. What materials become
> brittle after 2 years in deep space? How do computer systems
> resist? How about the water recycling machines, the CO2 extracting
> machines, etc?
All of this can be done on ISS. No moon required.
> 3) Experience in deep space radiation hardening, effects of deep space
> radiation in living beings.
Already a solved problem. It's not like radiation, and radiation
shielding, isn't well understood by science. It's not hard for an
engineer to turn this science into a practical radiation shield for the
conditions expected.
> 4) Experience in developing autonomous "gardens" to provide for oxygen
> recycling and food for very long missions. The objective is to
> acquire know how to be able to fly 2 years producing food aboard
> instead of shipping everything from earth and forcing the crew to
> survive in canned food for years.
Mir and ISS experience applies here. Moon not necessary. As for food,
the mass budget can tolerate shipping all the food the crew needs.
Dehydrated food saves on mass, but may not be necessary (think MRE's)
depending on the mass budget.
> 5) Experience in building habitats for humans underground in another
> planet. Experience with testing building materials, machines that
> work at a percentage of gravity of the earth in deep space,
> resistance of the materials to radiation, etc.
Why would a habitat need to be underground? As for the other things,
the moon and Mars aren't the same (see the section on spacesuits above),
so the experience isn't directly transferable.
> And this list is by no means exhaustive.
This list is complete garbage.
> NOTE: Mars approaches Earth once every TWO earth years. The mission
> must be designed for at least 2 years.
>
> NOTE: I am speaking about DEEP space, not the space station
> environment that is still shielded from radiation by earth's
> magnetic field.
So? Engineers already know how to design a ship with adequate shielding
around a solar storm shelter (which would double as sleeping quarters).
Your big "problem" has already been solved.
Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer
>
> Le 13/05/13 00:28, Fred J. McCall a ï¿œcrit :
> > And just how does "experience in the moon" translate to either 6 month
> > long deep space flights OR spending time on Mars?
>
> In no particular order:
>
> 1) Experience in space-suits design/reliability
Sorry, no.
> > long deep space flights OR spending time on Mars?
>
> In no particular order:
>
> 1) Experience in space-suits design/reliability
a. Cooling needs to be completely different since even the thin Mars
atmosphere prevents using water/ice sublimation for cooling (like is
done on the moon).
b. Lunar dust is extremely abrasive due to lack of wind (which is
present on Mars). So, solving the lunar dust abrasion problem is
"overkill" for Mars.
c. Mars gravity is much higher than the moon, so suits that work well
on the moon (e.g. Apollo suits) are far too heavy for Mars.
> 2) Experience in building reliable components that work for longer
> periods of time in deep space conditions. What materials become
> brittle after 2 years in deep space? How do computer systems
> resist? How about the water recycling machines, the CO2 extracting
> machines, etc?
> 3) Experience in deep space radiation hardening, effects of deep space
> radiation in living beings.
shielding, isn't well understood by science. It's not hard for an
engineer to turn this science into a practical radiation shield for the
conditions expected.
> 4) Experience in developing autonomous "gardens" to provide for oxygen
> recycling and food for very long missions. The objective is to
> acquire know how to be able to fly 2 years producing food aboard
> instead of shipping everything from earth and forcing the crew to
> survive in canned food for years.
the mass budget can tolerate shipping all the food the crew needs.
Dehydrated food saves on mass, but may not be necessary (think MRE's)
depending on the mass budget.
> 5) Experience in building habitats for humans underground in another
> planet. Experience with testing building materials, machines that
> work at a percentage of gravity of the earth in deep space,
> resistance of the materials to radiation, etc.
the moon and Mars aren't the same (see the section on spacesuits above),
so the experience isn't directly transferable.
> And this list is by no means exhaustive.
> NOTE: Mars approaches Earth once every TWO earth years. The mission
> must be designed for at least 2 years.
>
> NOTE: I am speaking about DEEP space, not the space station
> environment that is still shielded from radiation by earth's
> magnetic field.
around a solar storm shelter (which would double as sleeping quarters).
Your big "problem" has already been solved.
Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer
Jeff Findley
May 13, 2013, 9:31:25 AM5/13/13
to
In article <kmql0d$8vt$1...@speranza.aioe.org>, ja...@spamsink.net says...
>
> Le 13/05/13 00:28, Fred J. McCall a ï¿œcrit :
trial and error, like you seem to think it is.
Sizing the cables on a suspension bridge uses the same equations, and
engineers have successfully built suspension bridges for a *long* time.
>
> Le 13/05/13 00:28, Fred J. McCall a ï¿œcrit :
> > That's because you're just a bit of a thickie.
>
> Unable to argue with any facts, Mr McCall just throws insults, as usual.
> I just took ONE proposal out of his hogwash and investigated it for 1
> hour. That time suffices to discover how hollow his assertions are.
>
> "Build a tether".
>
> Of course. Very easy.
It is, for an engineer. You're obviously not one. Engineering isn't
>
> Unable to argue with any facts, Mr McCall just throws insults, as usual.
> I just took ONE proposal out of his hogwash and investigated it for 1
> hour. That time suffices to discover how hollow his assertions are.
>
> "Build a tether".
>
> Of course. Very easy.
trial and error, like you seem to think it is.
Sizing the cables on a suspension bridge uses the same equations, and
engineers have successfully built suspension bridges for a *long* time.
Message has been deleted
Message has been deleted
jacob navia
May 13, 2013, 4:26:24 PM5/13/13
to
Le 13/05/13 17:48, Fred J. McCall a écrit :
>
> NOTE: You don't know what you're talking about.
>
Obviously.
You are right, I am wrong. End of story.
>
> NOTE: You don't know what you're talking about.
>
Obviously.
You are right, I am wrong. End of story.
bob haller
May 13, 2013, 5:46:02 PM5/13/13
to
Fred forgot the shuttle tether that didnt work ..........
fred is a ignorant loon who disses near everything except his dream
ideas
fred is a ignorant loon who disses near everything except his dream
ideas
jacob navia
May 13, 2013, 6:12:19 PM5/13/13
to
Le 13/05/13 15:31, Jeff Findley a écrit :
>> Le 13/05/13 00:28, Fred J. McCall a écrit :
There I cited
http://www.gizmag.com/esa-space-tether/26879/
<quote>
broken by micrometeoroids.
<end quote>
Of course the equations are known. Also known is the strength of a cable
with a given material and the equation of Newton about forces.
That is obviously NOT enough!
About HALF of the tethers fail even though the equations are well known!
Problems arise with UNEXPECTED CONDITIONS that provoke an overload of
the tether and it snaps. All those equations have ASSUMPTIONS in them
Obviously I am not in the tether construction business, that is why
I will rather believe what the experts and the track record of tethers
SHOWS instead of hollow suppositions here without any data to back them
up.
If the equations are so easy and there is a lot of experience building
bridges why is it that still the tethers snap as the experiment with the
space shuttle showed?
Or are you saying that the people that built that failed tether weren't
engineers?
You, and Mr McCall haven't shown any single fact that would give your
thesis any weight.
You say:
errors, false solutions and enormous failures. Obviously there is
a mathematical background but that leads you only partway. The rest
is trial and error yes.
Before all those bridges were built there were a LOT of those that
failed miserably didn't you know?
The only difference is that NOW we have finished the trial and error
phase.
FOR BRIDGES!
For space tethers it hasn't even BEGUN.
jacob
>> Le 13/05/13 00:28, Fred J. McCall a écrit :
>>> That's because you're just a bit of a thickie.
>>
>> Unable to argue with any facts, Mr McCall just throws insults, as usual.
>> I just took ONE proposal out of his hogwash and investigated it for 1
>> hour. That time suffices to discover how hollow his assertions are.
>>
>> "Build a tether".
>>
>> Of course. Very easy.
>
> It is, for an engineer. You're obviously not one. Engineering isn't
> trial and error, like you seem to think it is.
>
> Sizing the cables on a suspension bridge uses the same equations, and
> engineers have successfully built suspension bridges for a *long* time.
>
> Jeff
>
Did you even read my article in this discussion?
>>
>> Unable to argue with any facts, Mr McCall just throws insults, as usual.
>> I just took ONE proposal out of his hogwash and investigated it for 1
>> hour. That time suffices to discover how hollow his assertions are.
>>
>> "Build a tether".
>>
>> Of course. Very easy.
>
> It is, for an engineer. You're obviously not one. Engineering isn't
> trial and error, like you seem to think it is.
>
> Sizing the cables on a suspension bridge uses the same equations, and
> engineers have successfully built suspension bridges for a *long* time.
>
> Jeff
>
There I cited
http://www.gizmag.com/esa-space-tether/26879/
<quote>
The problem is, space tethers are a formidable engineering challenge.
They need to be thin, light and flexible in order to fit inside of a
spacecraft or launch vehicle, they need to be extremely long, they need
to be strong enough to support a payload as well as their own weight,
and, if they must transmit power or data, they need to maintain internal
integrity. In other words, it doesn't help if the tether doesn’t break
They need to be thin, light and flexible in order to fit inside of a
spacecraft or launch vehicle, they need to be extremely long, they need
to be strong enough to support a payload as well as their own weight,
and, if they must transmit power or data, they need to maintain internal
if the electric wire inside snaps. At the moment, experimental tethers
haven’t had a great track record. About half fail to deploy, snap or are
broken by micrometeoroids.
<end quote>
Of course the equations are known. Also known is the strength of a cable
with a given material and the equation of Newton about forces.
That is obviously NOT enough!
About HALF of the tethers fail even though the equations are well known!
Problems arise with UNEXPECTED CONDITIONS that provoke an overload of
the tether and it snaps. All those equations have ASSUMPTIONS in them
Obviously I am not in the tether construction business, that is why
I will rather believe what the experts and the track record of tethers
SHOWS instead of hollow suppositions here without any data to back them
up.
If the equations are so easy and there is a lot of experience building
bridges why is it that still the tethers snap as the experiment with the
space shuttle showed?
Or are you saying that the people that built that failed tether weren't
engineers?
You, and Mr McCall haven't shown any single fact that would give your
thesis any weight.
You say:
> Engineering isn't
> trial and error, like you seem to think it is.
Engineering is not a science Mr. It is an art that is paved with
> trial and error, like you seem to think it is.
errors, false solutions and enormous failures. Obviously there is
a mathematical background but that leads you only partway. The rest
is trial and error yes.
Before all those bridges were built there were a LOT of those that
failed miserably didn't you know?
The only difference is that NOW we have finished the trial and error
phase.
FOR BRIDGES!
For space tethers it hasn't even BEGUN.
jacob
bob haller
May 13, 2013, 10:23:37 PM5/13/13
to
On May 13, 6:12 pm, jacob navia <ja...@spamsink.net> wrote:
> Le 13/05/13 15:31, Jeff Findley a écrit :
>
>
>
>
>
> > In article <kmql0d$8v...@speranza.aioe.org>, ja...@spamsink.net says...
> Le 13/05/13 15:31, Jeff Findley a écrit :
>
>
>
>
>
>
> >> Le 13/05/13 00:28, Fred J. McCall a écrit :
> >>> That's because you're just a bit of a thickie.
>
> >> Unable to argue with any facts, Mr McCall just throws insults, as usual.
> >> I just took ONE proposal out of his hogwash and investigated it for 1
> >> hour. That time suffices to discover how hollow his assertions are.
>
> >> "Build a tether".
>
> >> Of course. Very easy.
>
> > It is, for an engineer. You're obviously not one. Engineering isn't
> > trial and error, like you seem to think it is.
>
> > Sizing the cables on a suspension bridge uses the same equations, and
> > engineers have successfully built suspension bridges for a *long* time.
>
> > Jeff
>
> Did you even read my article in this discussion?
>
> There I citedhttp://www.gizmag.com/esa-space-tether/26879/
> >> Le 13/05/13 00:28, Fred J. McCall a écrit :
> >>> That's because you're just a bit of a thickie.
>
> >> Unable to argue with any facts, Mr McCall just throws insults, as usual.
> >> I just took ONE proposal out of his hogwash and investigated it for 1
> >> hour. That time suffices to discover how hollow his assertions are.
>
> >> "Build a tether".
>
> >> Of course. Very easy.
>
> > It is, for an engineer. You're obviously not one. Engineering isn't
> > trial and error, like you seem to think it is.
>
> > Sizing the cables on a suspension bridge uses the same equations, and
> > engineers have successfully built suspension bridges for a *long* time.
>
> > Jeff
>
> Did you even read my article in this discussion?
>
a wierd ride to no where.
Message has been deleted
Message has been deleted
Message has been deleted
Wayne Throop
May 14, 2013, 3:25:27 AM5/14/13
to
:: bob haller <hal...@aol.com>
:: Fred forgot the shuttle tether that didnt work ..........
: Fred J. McCall <fjmc...@gmail.com>
: And just how do you know that, Bobbert?
Seems much more likely that Fred remembered why the tether broke, and the
fact that it was an electrodynamic tether just chock full of conductive
materials and faulty insulation for that purpose, and not designed for
(nor fail because of a lack of) tensile strength.
Or he remembered that a spin tether would most likely be only a few
hundred meters long at most, while the electrodynamic tether failed
due to insulation breakdown after many miles had been deployed. A spin
tether for a mars mission could conceivably be mis-designed or have a
manufacturing flaw. But the electrodynamic thether failure didn't show
that a spin tether failure is any more than infinitessimally likely.
None of the failing elements would even *exist* in a spin tether.
Could you at least *try* to find a relevant example, hellerb?
Something at a comparable length, designed for a comparable purpose?
:: Fred forgot the shuttle tether that didnt work ..........
: Fred J. McCall <fjmc...@gmail.com>
: And just how do you know that, Bobbert?
Seems much more likely that Fred remembered why the tether broke, and the
fact that it was an electrodynamic tether just chock full of conductive
materials and faulty insulation for that purpose, and not designed for
(nor fail because of a lack of) tensile strength.
Or he remembered that a spin tether would most likely be only a few
hundred meters long at most, while the electrodynamic tether failed
due to insulation breakdown after many miles had been deployed. A spin
tether for a mars mission could conceivably be mis-designed or have a
manufacturing flaw. But the electrodynamic thether failure didn't show
that a spin tether failure is any more than infinitessimally likely.
None of the failing elements would even *exist* in a spin tether.
Could you at least *try* to find a relevant example, hellerb?
Something at a comparable length, designed for a comparable purpose?
jacob navia
May 14, 2013, 4:07:06 AM5/14/13
to
Le 14/05/13 09:25, Wayne Throop a �crit :
> Could you at least*try* to find a relevant example, hellerb?
never been attempted before. Tethers are used for electromagnetic
appliations or momentum transfer but never at the scale needed by
artificial gravity in a real spaceship!
We go into uncharted territory.
You say:
... a spin tether would most likely be only a few
dampening vibrations specially when they could be in resonance with the
length of the tether.
As you know soldiers don't walk in lock step in a bridge.
But in a real spaceship motors and other components are very prone to
repetitive frequencies that could match the main resonance frequency in
the tether/spaceship configuration or some harmonic.
I am not saying this is an insurmontable problem or that "it can't be
done". I am saying that this has never been even *attempted* before.
Nothing more, but nothing less either.
In general manned spaceflight has been shut down and governments
are spending their monnies in more important things like bank bailouts
or some wars.
What I am saying is that putting reasonable and attainable objectives
is much more likely to succeed than "bold" ideas to go to Mars when
it is plain obvious that the enormous expenditure needed is very
difficult to obtain.
A trip to the moon *is* possible and the moon is completely unexplored.
A lot of things could be waiting for us there. We have precisely
*no idea*
of what is there.
> Could you at least*try* to find a relevant example, hellerb?
> Something at a comparable length, designed for a comparable purpose?
That's precisely the problem. Artificial gravity with tethers has
never been attempted before. Tethers are used for electromagnetic
appliations or momentum transfer but never at the scale needed by
artificial gravity in a real spaceship!
We go into uncharted territory.
You say:
... a spin tether would most likely be only a few
hundred meters long at most, while the electrodynamic tether failed
due to insulation breakdown after many miles had been deployed.
Other problems arise in that configuration, for instance the problem of
due to insulation breakdown after many miles had been deployed.
dampening vibrations specially when they could be in resonance with the
length of the tether.
As you know soldiers don't walk in lock step in a bridge.
But in a real spaceship motors and other components are very prone to
repetitive frequencies that could match the main resonance frequency in
the tether/spaceship configuration or some harmonic.
I am not saying this is an insurmontable problem or that "it can't be
done". I am saying that this has never been even *attempted* before.
Nothing more, but nothing less either.
In general manned spaceflight has been shut down and governments
are spending their monnies in more important things like bank bailouts
or some wars.
What I am saying is that putting reasonable and attainable objectives
is much more likely to succeed than "bold" ideas to go to Mars when
it is plain obvious that the enormous expenditure needed is very
difficult to obtain.
A trip to the moon *is* possible and the moon is completely unexplored.
A lot of things could be waiting for us there. We have precisely
*no idea*
of what is there.
bob haller
May 14, 2013, 8:28:45 AM5/14/13
to
cost doesnt matter?
this would explain his belief you just build it. without consideration
of how difficult it might be
Jeff Findley
May 14, 2013, 8:43:27 AM5/14/13
to
In article <85eb73ff-fa77-41f8-a7dd-0a5215eb1eb7
@l5g2000vbn.googlegroups.com>, hal...@aol.com says...
than one tether missions/experiments over the years. If dim memory is
correct, these date back to a manned Gemini mission.
If you're asserting that engineers don't know enough by now to design,
build, and fly a tether for a manned Mars mission, then please back that
up. One extremely vague data point from your addled memory doesn't
count for much, if anything.
@l5g2000vbn.googlegroups.com>, hal...@aol.com says...
>
> Fred forgot the shuttle tether that didnt work ..........
>
> fred is a ignorant loon who disses near everything except his dream
> ideas
Fred did no such thing. Please don't forget that there has been more
> Fred forgot the shuttle tether that didnt work ..........
>
> fred is a ignorant loon who disses near everything except his dream
> ideas
than one tether missions/experiments over the years. If dim memory is
correct, these date back to a manned Gemini mission.
If you're asserting that engineers don't know enough by now to design,
build, and fly a tether for a manned Mars mission, then please back that
up. One extremely vague data point from your addled memory doesn't
count for much, if anything.
Jeff Findley
May 14, 2013, 8:50:48 AM5/14/13
to
In article <kmsrb8$p6s$1...@speranza.aioe.org>, ja...@spamsink.net says...
>
> Le 14/05/13 09:25, Wayne Throop a ï¿œcrit :
the Agena's docking collar. The "artificial gravity" produced was
admittedly very small (about 0.00015 g), but saying it's *never* been
attempted isn't correct.
> We go into uncharted territory.
>
> You say:
>
> ... a spin tether would most likely be only a few
> hundred meters long at most, while the electrodynamic tether failed
> due to insulation breakdown after many miles had been deployed.
>
> Other problems arise in that configuration, for instance the problem of
> dampening vibrations specially when they could be in resonance with the
> length of the tether.
Dynamics and control have gotten quite good over the years. Worst case,
I'd think you'd need active control of both the manned module and the
spin mass. If the spin mass is the spent stage used to send the craft
on its way to Mars, it would be no great trick to use its reaction
control engines to this end.
> As you know soldiers don't walk in lock step in a bridge.
>
> But in a real spaceship motors and other components are very prone to
> repetitive frequencies that could match the main resonance frequency in
> the tether/spaceship configuration or some harmonic.
>
> I am not saying this is an insurmontable problem or that "it can't be
> done". I am saying that this has never been even *attempted* before.
>
> Nothing more, but nothing less either.
>
> In general manned spaceflight has been shut down and governments
> are spending their monnies in more important things like bank bailouts
> or some wars.
>
> What I am saying is that putting reasonable and attainable objectives
> is much more likely to succeed than "bold" ideas to go to Mars when
> it is plain obvious that the enormous expenditure needed is very
> difficult to obtain.
>
> A trip to the moon *is* possible and the moon is completely unexplored.
> A lot of things could be waiting for us there. We have precisely
>
> *no idea*
>
> of what is there.
Going back to the moon seems counter intuitive if we have less to learn
than Mars. Add to that the fact that *not* a very good "stepping
stone" to Mars since the two environments are *very* different and there
is little to no reason to go back to the Moon, especially if Mars is the
next large body to explore.
>
> Le 14/05/13 09:25, Wayne Throop a ï¿œcrit :
> > Could you at least*try* to find a relevant example, hellerb?
> > Something at a comparable length, designed for a comparable purpose?
>
> That's precisely the problem. Artificial gravity with tethers has
> never been attempted before. Tethers are used for electromagnetic
> appliations or momentum transfer but never at the scale needed by
> artificial gravity in a real spaceship!
It was attempted on Gemini 11 with a 100-foot (30 m) tether, launched in
> > Something at a comparable length, designed for a comparable purpose?
>
> That's precisely the problem. Artificial gravity with tethers has
> never been attempted before. Tethers are used for electromagnetic
> appliations or momentum transfer but never at the scale needed by
> artificial gravity in a real spaceship!
the Agena's docking collar. The "artificial gravity" produced was
admittedly very small (about 0.00015 g), but saying it's *never* been
attempted isn't correct.
> We go into uncharted territory.
>
> You say:
>
> ... a spin tether would most likely be only a few
> hundred meters long at most, while the electrodynamic tether failed
> due to insulation breakdown after many miles had been deployed.
>
> Other problems arise in that configuration, for instance the problem of
> dampening vibrations specially when they could be in resonance with the
> length of the tether.
I'd think you'd need active control of both the manned module and the
spin mass. If the spin mass is the spent stage used to send the craft
on its way to Mars, it would be no great trick to use its reaction
control engines to this end.
> As you know soldiers don't walk in lock step in a bridge.
>
> But in a real spaceship motors and other components are very prone to
> repetitive frequencies that could match the main resonance frequency in
> the tether/spaceship configuration or some harmonic.
>
> I am not saying this is an insurmontable problem or that "it can't be
> done". I am saying that this has never been even *attempted* before.
>
> Nothing more, but nothing less either.
>
> In general manned spaceflight has been shut down and governments
> are spending their monnies in more important things like bank bailouts
> or some wars.
>
> What I am saying is that putting reasonable and attainable objectives
> is much more likely to succeed than "bold" ideas to go to Mars when
> it is plain obvious that the enormous expenditure needed is very
> difficult to obtain.
>
> A trip to the moon *is* possible and the moon is completely unexplored.
> A lot of things could be waiting for us there. We have precisely
>
> *no idea*
>
> of what is there.
than Mars. Add to that the fact that *not* a very good "stepping
stone" to Mars since the two environments are *very* different and there
is little to no reason to go back to the Moon, especially if Mars is the
next large body to explore.
Jeff Findley
May 14, 2013, 8:56:08 AM5/14/13
to
In article <d7cdd268-bc12-4536-82c5-636b28b966b4
@k5g2000vbq.googlegroups.com>, hal...@aol.com says...
while you have no clue. You're not an engineer. Stick to what you do
best, fixing machines that other people have designed, built, tested,
and deployed to the marketplace.
@k5g2000vbq.googlegroups.com>, hal...@aol.com says...
>
> perhaps fred is used to the unlimited budgets of the military where
> cost doesnt matter?
>
> this would explain his belief you just build it. without consideration
> of how difficult it might be
Fred has a hell of a lot better idea of "how difficult it might be",
> perhaps fred is used to the unlimited budgets of the military where
> cost doesnt matter?
>
> this would explain his belief you just build it. without consideration
> of how difficult it might be
while you have no clue. You're not an engineer. Stick to what you do
best, fixing machines that other people have designed, built, tested,
and deployed to the marketplace.
Jeff Findley
May 14, 2013, 9:12:33 AM5/14/13
to
In article <kmrog3$rp$1...@speranza.aioe.org>, ja...@spamsink.net says...
super light massed tether intended for a solar sail application,
deployed on a very tiny massed "cubesat") is *not* the same type of
tether you'd used to spin very large, quite massive, structures in space
like a manned Mars transit module.
Scaling laws apply here. It's going to be *a lot* easier to design a
far bigger, stronger, tether for a manned mission than this tiny wisp of
a tether for a "cubesat".
> You say:
> > Engineering isn't
> > trial and error, like you seem to think it is.
>
> Engineering is not a science Mr. It is an art that is paved with
> errors, false solutions and enormous failures. Obviously there is
> a mathematical background but that leads you only partway. The rest
> is trial and error yes.
>
> Before all those bridges were built there were a LOT of those that
> failed miserably didn't you know?
>
> The only difference is that NOW we have finished the trial and error
> phase.
>
> FOR BRIDGES!
>
> For space tethers it hasn't even BEGUN.
The business of commercial finite element analysis (FEA) software has
been around for about five decades. To say that "there is a
mathematical background but that leads you only partway" shows your
ignorance of the industry.
I write FEA code for a living (it's my full-time job since 1992). Much
of the FEA industry has its roots in a software package called Nastran
originally developed by government funding in the 1960's by a company
called MacNeal-Schwendler Corporation (MSC).
Nastran
http://en.wikipedia.org/wiki/Nastran
The company I have worked for (since I was an engineering co-op student
starting in the late 1980's) has changed hands and names over the years,
but it started as SDRC (in the late 60's) and is now owned by Siemens
AG.
SDRC
http://en.wikipedia.org/wiki/SDRC
For the last 10 plus years, I've worked on NX Simulation (FEA) software:
NX (Unigraphics)
http://en.wikipedia.org/wiki/NX_%28Unigraphics%29
I think my professional experience says I know a bit more about the
"mathematical background" of engineering than you.
>
> Did you even read my article in this discussion?
Of course I did, but the type of tether talked about in the article (a
> Did you even read my article in this discussion?
super light massed tether intended for a solar sail application,
deployed on a very tiny massed "cubesat") is *not* the same type of
tether you'd used to spin very large, quite massive, structures in space
like a manned Mars transit module.
Scaling laws apply here. It's going to be *a lot* easier to design a
far bigger, stronger, tether for a manned mission than this tiny wisp of
a tether for a "cubesat".
> You say:
> > Engineering isn't
> > trial and error, like you seem to think it is.
>
> Engineering is not a science Mr. It is an art that is paved with
> errors, false solutions and enormous failures. Obviously there is
> a mathematical background but that leads you only partway. The rest
> is trial and error yes.
>
> Before all those bridges were built there were a LOT of those that
> failed miserably didn't you know?
>
> The only difference is that NOW we have finished the trial and error
> phase.
>
> FOR BRIDGES!
>
> For space tethers it hasn't even BEGUN.
been around for about five decades. To say that "there is a
mathematical background but that leads you only partway" shows your
ignorance of the industry.
I write FEA code for a living (it's my full-time job since 1992). Much
of the FEA industry has its roots in a software package called Nastran
originally developed by government funding in the 1960's by a company
called MacNeal-Schwendler Corporation (MSC).
Nastran
http://en.wikipedia.org/wiki/Nastran
The company I have worked for (since I was an engineering co-op student
starting in the late 1980's) has changed hands and names over the years,
but it started as SDRC (in the late 60's) and is now owned by Siemens
AG.
SDRC
http://en.wikipedia.org/wiki/SDRC
For the last 10 plus years, I've worked on NX Simulation (FEA) software:
NX (Unigraphics)
http://en.wikipedia.org/wiki/NX_%28Unigraphics%29
I think my professional experience says I know a bit more about the
"mathematical background" of engineering than you.
Jeff Findley
May 14, 2013, 9:15:43 AM5/14/13
to
In article <ca5905ea-1958-4a66-985f-24e0ea7921be@
12g2000vba.googlegroups.com>, hal...@aol.com says...
do you? Sad, really.
12g2000vba.googlegroups.com>, hal...@aol.com says...
>
> imagine a cable breaking and the human portion going off by itself on
> a wierd ride to no where.
You still have no clue about structural engineering or orbital mechanics
> imagine a cable breaking and the human portion going off by itself on
> a wierd ride to no where.
do you? Sad, really.
Message has been deleted
Wayne Throop
May 14, 2013, 11:55:28 AM5/14/13
to
: jacob navia <ja...@spamsink.net>
: Other problems arise in that configuration, for instance the problem
lost as humans head into space. Just like seat belts and fuses.
: As you know soldiers don't walk in lock step in a bridge.
True, all the soldiers that we expect to be marching up
and down the tether are an insurmountable problem.
http://en.wikipedia.org/wiki/MythBusters_(2004_season)
In the initial test, the soldiers moved far too slowly due to a
disconnected hose. During the second and third tests, the soldiers
stomped too hard on the bridge, causing the bridge to collapse from
impact without any harmonic vibration.
http://en.wikipedia.org/wiki/Broughton_Suspension_Bridge
It emerged that three years previously the distinguished Manchester
engineer, Eaton Hodgkinson, had expressed some doubt about the
strength of the stay-chains compared with the suspension chains. He
had said that they should be rigorously tested, but they were
not.[7] It also came to light that some time before the accident one
of the cross bolts had started to bend and crack, although it was
believed to have been replaced by the time of the accident. The
conclusion was that, although the vibration caused by the marching
had precipitated the bolt's failure, it would have happened
anyway.[5]
: I am not saying this is an insurmontable problem or that "it can't be
And if you want to do experiments, it's not really that difficult to
arrange to test tethers on the ground, one way or another. True, you'd
end up with the "gravity" pointed at an angle in the masses at the end
of the tether under test, but many of the obvious things can be tested
without substantial cost. Then, send up an experiment package to the ISS,
and have at it. It's not like it'd be a huge money sink, nor take all that
long, to get some engineering experience with such.
: What I am saying is that putting reasonable and attainable objectives
for spin gravity is not nearly so difficult and fraught-with-unknowns
as to be a significant risk factor.
: Other problems arise in that configuration, for instance the problem
: of dampening vibrations specially when they could be in resonance with
: the length of the tether.
And as we all know, the ability to damp harmonic vibrations will be
: the length of the tether.
lost as humans head into space. Just like seat belts and fuses.
: As you know soldiers don't walk in lock step in a bridge.
True, all the soldiers that we expect to be marching up
and down the tether are an insurmountable problem.
http://en.wikipedia.org/wiki/MythBusters_(2004_season)
In the initial test, the soldiers moved far too slowly due to a
disconnected hose. During the second and third tests, the soldiers
stomped too hard on the bridge, causing the bridge to collapse from
impact without any harmonic vibration.
http://en.wikipedia.org/wiki/Broughton_Suspension_Bridge
It emerged that three years previously the distinguished Manchester
engineer, Eaton Hodgkinson, had expressed some doubt about the
strength of the stay-chains compared with the suspension chains. He
had said that they should be rigorously tested, but they were
not.[7] It also came to light that some time before the accident one
of the cross bolts had started to bend and crack, although it was
believed to have been replaced by the time of the accident. The
conclusion was that, although the vibration caused by the marching
had precipitated the bolt's failure, it would have happened
anyway.[5]
: I am not saying this is an insurmontable problem or that "it can't be
: done". I am saying that this has never been even *attempted* before.
However, dynamic structures under tension *have* been done before.
And if you want to do experiments, it's not really that difficult to
arrange to test tethers on the ground, one way or another. True, you'd
end up with the "gravity" pointed at an angle in the masses at the end
of the tether under test, but many of the obvious things can be tested
without substantial cost. Then, send up an experiment package to the ISS,
and have at it. It's not like it'd be a huge money sink, nor take all that
long, to get some engineering experience with such.
: What I am saying is that putting reasonable and attainable objectives
: is much more likely to succeed than "bold" ideas to go to Mars when it
: is plain obvious that the enormous expenditure needed is very
: difficult to obtain.
I'm not advocating going to mars. I'm simply saying that use of tethers
: is plain obvious that the enormous expenditure needed is very
: difficult to obtain.
for spin gravity is not nearly so difficult and fraught-with-unknowns
as to be a significant risk factor.
Wrong Stuff
May 14, 2013, 5:04:39 PM5/14/13
to
to go on the cheap. Perhaps it can be an elegant solution BUT a different
solution might solve some of the other problems of a deep space human rated
craft.
The more massive the craft, the less passive shielding as a percent of
the craft it would seem to me. Granted this means a really massive craft
but it could be THE one craft ferrying humans across the solar system at least
for starting up colonizing. I see it as an issue of infrastructure in part and efficient jumps off the rock and into orbit.
Indeed, Mars would seem to be the better jumping of spot at some point
in the future. Nuclear power craft could be kept largely clear of Earth.
Perhaps the Earth to Mars and back again should be something other than
nuclear given human ability to botch things up and do stupid things.
the rhino's tail is trying to hit me so I've got to buzz...........Trig
bob haller
May 14, 2013, 9:45:41 PM5/14/13
to
>
> I'm not advocating going to mars. I'm simply saying that use of tethers
> for spin gravity is not nearly so difficult and fraught-with-unknowns
> as to be a significant risk factor.
oxygen rich atmosphere during ground testing........
till apollo one burned on the pad.......
tethers that have never been tested might have its own issues that no
one knows yet:(
they need to do some testing before departing for mars.....
Just saying something will work needs extensive testing
bob haller
May 14, 2013, 9:53:06 PM5/14/13
to
I believe shortening the transit time dramatically along with
shielding the manned part is better than adding the complexity of a
tether.
The longer the transit time the more spares, food, water, and risk
from breakdowns. Which makes the vehicle bigger...
So a nuclear booster for use for transit saves needing a tether, and
minimizes all the items of supply....
NERVA was in development, its time to go dust off those ideas......
shielding the manned part is better than adding the complexity of a
tether.
The longer the transit time the more spares, food, water, and risk
from breakdowns. Which makes the vehicle bigger...
So a nuclear booster for use for transit saves needing a tether, and
minimizes all the items of supply....
NERVA was in development, its time to go dust off those ideas......
Wayne Throop
May 14, 2013, 10:14:02 PM5/14/13
to
: bob haller <hal...@aol.com>
: Back during the early Apollo program no one gave much thought to a
Tethers far far far less so. Oxygen, in the crew compartment with
the crew. Tether, outside in space. So basically, your choice of
a risk to compare it too was very bad indeed. Based on the nature of
the beast and accident rates with beasts of similar nature, tethers
can quite confidently be considered several orders of magnitude less
risky than tanks or crew com partments filled with reactive chemicals.
So again, tethers wouldn't be the things to be worrying about.
You may claim "it's never been done!". Fair enough. But every step you
take on an unfamiliar road "hasn't been done!", either. The question is,
how difficult or risky are similar steps in similar trips. And basically,
by pushing tethers as a risk factor, you're just showing that you're
wildly risk-averse, far more than the actual risks justify... except
for items on your own pet projects; then any risk is Just Fine.
: Back during the early Apollo program no one gave much thought to a
: oxygen rich atmosphere during ground testing........
Well let's see if that's relevant. Oxygen, chemically active (very).
Tethers far far far less so. Oxygen, in the crew compartment with
the crew. Tether, outside in space. So basically, your choice of
a risk to compare it too was very bad indeed. Based on the nature of
the beast and accident rates with beasts of similar nature, tethers
can quite confidently be considered several orders of magnitude less
risky than tanks or crew com partments filled with reactive chemicals.
So again, tethers wouldn't be the things to be worrying about.
You may claim "it's never been done!". Fair enough. But every step you
take on an unfamiliar road "hasn't been done!", either. The question is,
how difficult or risky are similar steps in similar trips. And basically,
by pushing tethers as a risk factor, you're just showing that you're
wildly risk-averse, far more than the actual risks justify... except
for items on your own pet projects; then any risk is Just Fine.
Wayne Throop
May 14, 2013, 10:20:29 PM5/14/13
to
: bob haller <hal...@aol.com>
: I believe shortening the transit time dramatically along with
of such a project.
: So a nuclear booster for use for transit saves needing a tether, and
more than space structures under tension. And they're so much simpler
than a tether, ie, a cable. Yep, those simple "nuclear boosters" that
everybody knows are so reliable are *lots* simpler than a cable.
And so much less engineering to create a "nuclear booster", too.
And bound to be as safe as the day is long. Safer, even.
But seriously, if anybody concludes a cable is more complex and less
reliable than a nuclear reaction motor, they need to get out more.
Or need *some*thing.
And if you can do arithmetic, you'd see that "minimizing the items of
supply" when you're talking the extra reaction mass for extra delta-v
and reactor sheilding and reactor fuel, is not really solving
any significant problems.
: NERVA was in development, its time to go dust off those ideas......
NERVA doesn't have *enough* ISP improvement to be the magic wand that
solves all the problems. It wouldn't reduce the transit times to avoid
sheielding issues and would even add sheilding issues of its own. And it
wouldn't reduce the consumables enough to make it clearly superior. And
it wouldn't shorting transit times enough to solve bone density and
muscle mass losses. NERVA-style nuclear thermal rockets aren't constant
acceleration torchships.
Not that I'm against nuclear thermal rockets. I'm just against
claiming they solve the problems you say they do, and (for the
reasonable duration futurewards) they are safer than tethers.
It's like "gee, those rapelling and climbing ropes look awaful unsafe...
I know! I'll just set myself on fire and shoot myself out of a gunpowder
cannon! That'll save all the safety issues and keep me warm on the
mountaintop to boot! And get me to the top of the mountain faster, too!"
So what have we learned? Well, that hallerb is massively, incredibly,
overwhelmingly risk-averse when it's a simple technology like a cable,
but massively, incredibly, overwhelmingly risk-tolerant, as well as
extremely results-optimistic (ie, gulible) if it's a complex technology
that captures his fancy, like a nuclear thermal rocket.
And by the way, if nuclear reactors are so unsafe (as you claim in
multidudinous postings), why is it the technology of choice
for space travel?
Somebody, anybody, everybody, SCREAM!"
--- opening line of "Squirrels in My Pants"
: I believe shortening the transit time dramatically along with
: shielding the manned part is better than adding the complexity of a
: tether.
An excellent summary of why you shouldn't be left in charge
: tether.
of such a project.
: So a nuclear booster for use for transit saves needing a tether, and
: minimizes all the items of supply....
Because "nuclear boosters" have been done so often before, many times
more than space structures under tension. And they're so much simpler
than a tether, ie, a cable. Yep, those simple "nuclear boosters" that
everybody knows are so reliable are *lots* simpler than a cable.
And so much less engineering to create a "nuclear booster", too.
And bound to be as safe as the day is long. Safer, even.
But seriously, if anybody concludes a cable is more complex and less
reliable than a nuclear reaction motor, they need to get out more.
Or need *some*thing.
And if you can do arithmetic, you'd see that "minimizing the items of
supply" when you're talking the extra reaction mass for extra delta-v
and reactor sheilding and reactor fuel, is not really solving
any significant problems.
: NERVA was in development, its time to go dust off those ideas......
NERVA doesn't have *enough* ISP improvement to be the magic wand that
solves all the problems. It wouldn't reduce the transit times to avoid
sheielding issues and would even add sheilding issues of its own. And it
wouldn't reduce the consumables enough to make it clearly superior. And
it wouldn't shorting transit times enough to solve bone density and
muscle mass losses. NERVA-style nuclear thermal rockets aren't constant
acceleration torchships.
Not that I'm against nuclear thermal rockets. I'm just against
claiming they solve the problems you say they do, and (for the
reasonable duration futurewards) they are safer than tethers.
It's like "gee, those rapelling and climbing ropes look awaful unsafe...
I know! I'll just set myself on fire and shoot myself out of a gunpowder
cannon! That'll save all the safety issues and keep me warm on the
mountaintop to boot! And get me to the top of the mountain faster, too!"
So what have we learned? Well, that hallerb is massively, incredibly,
overwhelmingly risk-averse when it's a simple technology like a cable,
but massively, incredibly, overwhelmingly risk-tolerant, as well as
extremely results-optimistic (ie, gulible) if it's a complex technology
that captures his fancy, like a nuclear thermal rocket.
And by the way, if nuclear reactors are so unsafe (as you claim in
multidudinous postings), why is it the technology of choice
for space travel?
Somebody, anybody, everybody, SCREAM!"
--- opening line of "Squirrels in My Pants"
Message has been deleted
Message has been deleted
Jochem Huhmann
May 15, 2013, 5:43:17 AM5/15/13
to
thr...@sheol.org (Wayne Throop) writes:
> But seriously, if anybody concludes a cable is more complex and less
> reliable than a nuclear reaction motor, they need to get out more.
> Or need *some*thing.
A cable in itself may be dead simple, but having two parts rotating
> But seriously, if anybody concludes a cable is more complex and less
> reliable than a nuclear reaction motor, they need to get out more.
> Or need *some*thing.
creates a lot of problems that aren't exactly trivial either. You still
need to point your antennas and solar panels the right way, you may have
to do minor course corrections which are very hard to do without
stopping the rotation and docking the components, an EVA would be a
nightmare, having gravity in very cramped quarters has not only
advantages, the psychological effects of having the universe rotate
around you all the time when you look out of a window are unknown, and
so on.
Personally I would rather
Jochem
--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery
bob haller
May 15, 2013, 6:30:06 AM5/15/13
to
http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-111650317.html
nasas mars missions are 2 years long...
nasas mars missions are 2 years long...
bob haller
May 15, 2013, 6:35:08 AM5/15/13
to
On May 15, 6:30 am, bob haller <hall...@aol.com> wrote:
> http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-...
explore much beyond Earth," John Slough, a UW research associate
professor of aeronautics and astronautics, said in a statement. "We
are hoping to give us a much more powerful source of energy in space
that could eventually lead to making interplanetary travel
commonplace."
Previous estimates have found that a roundtrip manned mission to Mars
would require about 500 days of space travel. Slough, who is president
of MSNW, and his colleagues calculated that a rocket powered by fusion
would make 30- and 90-day expeditions to Mars possible. The project is
funded in part through NASA's Innovative Advanced Concepts Program and
received a second round of funding under the program in March.
For comparison, past NASA studies have centered on Mars flights that
would take two years to complete, and could cost $12 billion just to
launch the fuel needed for the mission, according to Slough's team.
> http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-...
>
> nasas mars missions are 2 years long...
Using existing rocket fuels, it's nearly impossible for humans to
> nasas mars missions are 2 years long...
explore much beyond Earth," John Slough, a UW research associate
professor of aeronautics and astronautics, said in a statement. "We
are hoping to give us a much more powerful source of energy in space
that could eventually lead to making interplanetary travel
commonplace."
Previous estimates have found that a roundtrip manned mission to Mars
would require about 500 days of space travel. Slough, who is president
of MSNW, and his colleagues calculated that a rocket powered by fusion
would make 30- and 90-day expeditions to Mars possible. The project is
funded in part through NASA's Innovative Advanced Concepts Program and
received a second round of funding under the program in March.
For comparison, past NASA studies have centered on Mars flights that
would take two years to complete, and could cost $12 billion just to
launch the fuel needed for the mission, according to Slough's team.
Message has been deleted
Message has been deleted
Jeff Findley
May 15, 2013, 1:03:10 PM5/15/13
to
In article <1e70aa6d-612a-4dad-8d4d-
400d2f...@eo6g2000vbb.googlegroups.com>, hal...@aol.com says...
> The longer the transit time the more spares, food, water, and risk
> from breakdowns. Which makes the vehicle bigger...
>
> So a nuclear booster for use for transit saves needing a tether, and
> minimizes all the items of supply....
>
> NERVA was in development, its time to go dust off those ideas......
So you want to trade spare parts, food, and water for a freaking
"nuclear booster"? You'd think that the very idea would send your
chicken little brain into meltdown.
Seriously though, we know how to make and store spare parts, food, and
water. We know how to increase the delta-V of chemical stages (add more
fuel and oxidizer tanks and drop them when empty). We don't quite know
how to make a safe nuclear rocket engine.
400d2f...@eo6g2000vbb.googlegroups.com>, hal...@aol.com says...
>
> I believe shortening the transit time dramatically along with
> shielding the manned part is better than adding the complexity of a
> tether.
Faith based engineering Bob? Seriously?
> I believe shortening the transit time dramatically along with
> shielding the manned part is better than adding the complexity of a
> tether.
> The longer the transit time the more spares, food, water, and risk
> from breakdowns. Which makes the vehicle bigger...
>
> So a nuclear booster for use for transit saves needing a tether, and
> minimizes all the items of supply....
>
> NERVA was in development, its time to go dust off those ideas......
"nuclear booster"? You'd think that the very idea would send your
chicken little brain into meltdown.
Seriously though, we know how to make and store spare parts, food, and
water. We know how to increase the delta-V of chemical stages (add more
fuel and oxidizer tanks and drop them when empty). We don't quite know
how to make a safe nuclear rocket engine.
Jeff Findley
May 15, 2013, 1:07:01 PM5/15/13
to
In article <9g17p8l5n1hpmhbdt...@4ax.com>,
fjmc...@gmail.com says...
>
> bob haller <hal...@aol.com> wrote:
> for him getting a working drive out of his theories.
My guess is that he's being deliberately disingenuous to "sell" his
research. This isn't he first time we've seen this in aerospace. How
about pushing research into hypersonic air breathing engines promising
such engines could be used on a reusable vehicle to launch payloads into
orbit?
fjmc...@gmail.com says...
>
> bob haller <hal...@aol.com> wrote:
>
> >On May 15, 6:30ï¿œam, bob haller <hall...@aol.com> wrote:
> >> http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-...
> >>
> >> nasas mars missions are 2 years long...
> >
> >"Using existing rocket fuels, it's nearly impossible for humans to
> >explore much beyond Earth," John Slough, a UW research associate
> >professor of aeronautics and astronautics, said in a statement.
> >
>
> And given that he's that wrong about that, I don't hold out much hope
> >On May 15, 6:30ï¿œam, bob haller <hall...@aol.com> wrote:
> >> http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-...
> >>
> >> nasas mars missions are 2 years long...
> >
> >"Using existing rocket fuels, it's nearly impossible for humans to
> >explore much beyond Earth," John Slough, a UW research associate
> >professor of aeronautics and astronautics, said in a statement.
> >
>
> for him getting a working drive out of his theories.
My guess is that he's being deliberately disingenuous to "sell" his
research. This isn't he first time we've seen this in aerospace. How
about pushing research into hypersonic air breathing engines promising
such engines could be used on a reusable vehicle to launch payloads into
orbit?
Wayne Throop
May 15, 2013, 2:42:36 PM5/15/13
to
:: http://news.yahoo.com/nuclear-fusion-rocket-could-reach-mars-30-days-111650317.html
: Fred J. McCall <fjmc...@gmail.com>
: This cuts the trip time by 5 months each way, so the trip is still 20
: months (almost two years). DOH!
Ah, but that's comparing apples to apples. Where's the fun in that?
Compare the apples of just-the-trip-time to the pineapples of
trip-plus-mars-surface time. Much more fun that way.
Also much more lame, but whatever.
: Other than that, I'll merely note that this is NOT the NERVA nuclear
: thermal rocket you've been pushing up to now and that this is all new
: and speculative technology. Don't hold your breath waiting for this
: to work.
And according to the article, they haven't even gotten fusion on a lab
bench yet. They've got "lab tests suggest" and "a powerful magnetic
field could be used", yada yada.
And if you've got a crewed spacecraft waiting for a surface team to complete
a mission, it might well need a spin tether anyways. You could just leave
it mothballed during the surface mission, but would you really want to
assume you could chirp it back to life with a keyfob after a year mothballed?
But it's the usual pattern. Take anything remotely realistic for the short
term, and hallerb becomes uber-risk-averse. Wave something shiny and
speculative, and he becomes hyper-uber-risk-tolerant.
: Fred J. McCall <fjmc...@gmail.com>
: This cuts the trip time by 5 months each way, so the trip is still 20
: months (almost two years). DOH!
Ah, but that's comparing apples to apples. Where's the fun in that?
Compare the apples of just-the-trip-time to the pineapples of
trip-plus-mars-surface time. Much more fun that way.
Also much more lame, but whatever.
: Other than that, I'll merely note that this is NOT the NERVA nuclear
: thermal rocket you've been pushing up to now and that this is all new
: and speculative technology. Don't hold your breath waiting for this
: to work.
And according to the article, they haven't even gotten fusion on a lab
bench yet. They've got "lab tests suggest" and "a powerful magnetic
field could be used", yada yada.
And if you've got a crewed spacecraft waiting for a surface team to complete
a mission, it might well need a spin tether anyways. You could just leave
it mothballed during the surface mission, but would you really want to
assume you could chirp it back to life with a keyfob after a year mothballed?
But it's the usual pattern. Take anything remotely realistic for the short
term, and hallerb becomes uber-risk-averse. Wave something shiny and
speculative, and he becomes hyper-uber-risk-tolerant.
Dr J R Stockton
May 15, 2013, 3:50:10 PM5/15/13
to
In sci.space.policy message <MPG.2bfbfd366...@news.eternal-
september.org>, Tue, 14 May 2013 08:50:48, Jeff Findley
<jeff.f...@nospam.ugs.com> posted:
>Going back to the moon seems counter intuitive if we have less to learn
>than Mars. Add to that the fact that *not* a very good "stepping
>stone" to Mars since the two environments are *very* different and there
>is little to no reason to go back to the Moon, especially if Mars is the
>next large body to explore.
The chief difficulty is the same for Moon and Mars, except that it is
harder for Mars. It is the obtaining of a reliable supply of sufficient
money.
Planning to go to the Moon would test whether any sufficient the present
generation has the motivation and capabilities that the forefathers of
the present US space industry lost forty years ago. Those plans need to
include a mission duration comparable with that required for Mars.
For Mars, ISTM reasonably likely that there is at least one acceptable
way of getting there more quickly and/or with less Earth Orbit departure
mass than would be the case for chemical propulsion; VASIMR seems a
candidate. Therefore, substantial effort should be put into developing
such propulsion speedily. It would not be needed for the Moon.
--
(c) John Stockton, nr London, UK. Mail via homepage. Turnpike v6.05 MIME.
Web <http://www.merlyn.demon.co.uk/> - FAQqish topics, acronyms and links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
september.org>, Tue, 14 May 2013 08:50:48, Jeff Findley
<jeff.f...@nospam.ugs.com> posted:
>Going back to the moon seems counter intuitive if we have less to learn
>than Mars. Add to that the fact that *not* a very good "stepping
>stone" to Mars since the two environments are *very* different and there
>is little to no reason to go back to the Moon, especially if Mars is the
>next large body to explore.
harder for Mars. It is the obtaining of a reliable supply of sufficient
money.
Planning to go to the Moon would test whether any sufficient the present
generation has the motivation and capabilities that the forefathers of
the present US space industry lost forty years ago. Those plans need to
include a mission duration comparable with that required for Mars.
For Mars, ISTM reasonably likely that there is at least one acceptable
way of getting there more quickly and/or with less Earth Orbit departure
mass than would be the case for chemical propulsion; VASIMR seems a
candidate. Therefore, substantial effort should be put into developing
such propulsion speedily. It would not be needed for the Moon.
--
(c) John Stockton, nr London, UK. Mail via homepage. Turnpike v6.05 MIME.
Web <http://www.merlyn.demon.co.uk/> - FAQqish topics, acronyms and links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
Jeff Findley
May 16, 2013, 9:26:21 AM5/16/13
to
In article <9tk5ALLy...@invalid.uk.co.demon.merlyn.invalid>,
repl...@merlyn.demon.co.uk.invalid says...
> Planning to go to the Moon would test whether any sufficient the present
> generation has the motivation and capabilities that the forefathers of
> the present US space industry lost forty years ago. Those plans need to
> include a mission duration comparable with that required for Mars.
But in this world of limited resources, once that money has been spent
on the moon, little is transferable to the Mars mission, so even if the
US has the political will to fund an expensive return to the moon, it
does *not* follow that they would support doing that again with Mars,
especially if they're honestly told that NASA needs to almost start over
and develop new landers, hab modules, spacesuits, power sources,
propellant plants (e.g. methane from Mars C02), engines (to burn the
methane), and etc.
Again, if the goal is to go to Mars, the moon is practically a dead end
and squandering scant resonances between two goals rather than one seems
rather silly.
> For Mars, ISTM reasonably likely that there is at least one acceptable
> way of getting there more quickly and/or with less Earth Orbit departure
> mass than would be the case for chemical propulsion; VASIMR seems a
> candidate. Therefore, substantial effort should be put into developing
> such propulsion speedily. It would not be needed for the Moon.
B.S. Chemical propulsion is all that is needed. Appropriate engines
either exist or are currently under development for such a task.
VASMIR isn't ready for such a big mission (in terms of mass to deliver
to Mars). Where do you get the *enormous* amount of electrical power
needed to run VASMIR engines of sufficient thrust for a manned Mars
mission? Nuclear? And this is supposed to save money? That would be
insanity on the level of Bob Haller.
There is no magic propulsion technology which will make going to Mars
*cheaper*.
repl...@merlyn.demon.co.uk.invalid says...
>
> In sci.space.policy message <MPG.2bfbfd366...@news.eternal-
> september.org>, Tue, 14 May 2013 08:50:48, Jeff Findley
> <jeff.f...@nospam.ugs.com> posted:
>
>
> >Going back to the moon seems counter intuitive if we have less to learn
> >than Mars. Add to that the fact that *not* a very good "stepping
> >stone" to Mars since the two environments are *very* different and there
> >is little to no reason to go back to the Moon, especially if Mars is the
> >next large body to explore.
>
> The chief difficulty is the same for Moon and Mars, except that it is
> harder for Mars. It is the obtaining of a reliable supply of sufficient
> money.
That issue they do have in common.
> In sci.space.policy message <MPG.2bfbfd366...@news.eternal-
> september.org>, Tue, 14 May 2013 08:50:48, Jeff Findley
> <jeff.f...@nospam.ugs.com> posted:
>
>
> >Going back to the moon seems counter intuitive if we have less to learn
> >than Mars. Add to that the fact that *not* a very good "stepping
> >stone" to Mars since the two environments are *very* different and there
> >is little to no reason to go back to the Moon, especially if Mars is the
> >next large body to explore.
>
> The chief difficulty is the same for Moon and Mars, except that it is
> harder for Mars. It is the obtaining of a reliable supply of sufficient
> money.
> Planning to go to the Moon would test whether any sufficient the present
> generation has the motivation and capabilities that the forefathers of
> the present US space industry lost forty years ago. Those plans need to
> include a mission duration comparable with that required for Mars.
on the moon, little is transferable to the Mars mission, so even if the
US has the political will to fund an expensive return to the moon, it
does *not* follow that they would support doing that again with Mars,
especially if they're honestly told that NASA needs to almost start over
and develop new landers, hab modules, spacesuits, power sources,
propellant plants (e.g. methane from Mars C02), engines (to burn the
methane), and etc.
Again, if the goal is to go to Mars, the moon is practically a dead end
and squandering scant resonances between two goals rather than one seems
rather silly.
> For Mars, ISTM reasonably likely that there is at least one acceptable
> way of getting there more quickly and/or with less Earth Orbit departure
> mass than would be the case for chemical propulsion; VASIMR seems a
> candidate. Therefore, substantial effort should be put into developing
> such propulsion speedily. It would not be needed for the Moon.
either exist or are currently under development for such a task.
VASMIR isn't ready for such a big mission (in terms of mass to deliver
to Mars). Where do you get the *enormous* amount of electrical power
needed to run VASMIR engines of sufficient thrust for a manned Mars
mission? Nuclear? And this is supposed to save money? That would be
insanity on the level of Bob Haller.
There is no magic propulsion technology which will make going to Mars
*cheaper*.
bob haller
May 16, 2013, 11:38:32 AM5/16/13
to
On May 16, 9:26 am, Jeff Findley <jeff.find...@nospam.ugs.com> wrote:
> In article <9tk5ALLyb+kRF...@invalid.uk.co.demon.merlyn.invalid>,
> reply1...@merlyn.demon.co.uk.invalid says...
>
>
>
> > In sci.space.policy message <MPG.2bfbfd36651106e5989...@news.eternal-
dont think cheap think possible.
a 3 year mission to mars isnt doable/
flags and footprints is a dead end think apollo.
the only practical one is nuke booster of some type to cut travel time
dramatically
> In article <9tk5ALLyb+kRF...@invalid.uk.co.demon.merlyn.invalid>,
> reply1...@merlyn.demon.co.uk.invalid says...
>
>
>
> > In sci.space.policy message <MPG.2bfbfd36651106e5989...@news.eternal-
> > september.org>, Tue, 14 May 2013 08:50:48, Jeff Findley
> > <jeff.find...@nospam.ugs.com> posted:
a 3 year mission to mars isnt doable/
flags and footprints is a dead end think apollo.
the only practical one is nuke booster of some type to cut travel time
dramatically
Greg (Strider) Moore
May 16, 2013, 2:19:54 PM5/16/13
to
"bob haller" wrote in message
news:45f119c9-099b-4519...@z8g2000yqd.googlegroups.com...
Look, it honestly comes down to a mass problem. Throw enough mass at the
problem and it gets easier. (and ironically in a sense cheaper).
Worried about shielding... bring lots of water. You'll need it anyway.
Water is cheap. Upmass isn't but it's getting cheaper.
Worried about breakdowns, bring redundancy and quantify the risk. At some
point you're going to have to kick the tires, light the engines and go
anyway.
Look, SpaceX launch prices are about $4K/kg to LEO. That's not cheap but
getting there. And that's their list price. I bet their costs are lower
and dropping.
If I did my math right and am stealing numbers from NASA's 2007 reference
mission, they want about 400mt to LEO.
So, 400,000*4,000 and I get $1.6B.
I'll double that since I'm conservative.
That's getting to the point where it's relatively cheap.
(give SpaceX a decade to get launch costs down another 50% and then we'll
see private folks doing it!)
>
--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
news:45f119c9-099b-4519...@z8g2000yqd.googlegroups.com...
>
>
>dont think cheap think possible.
>
<snip>
>
>dont think cheap think possible.
>
>the only practical one is nuke booster of some type to cut travel time
>dramatically
>
If you assume the first, you guarantee the second.
>dramatically
>
Look, it honestly comes down to a mass problem. Throw enough mass at the
problem and it gets easier. (and ironically in a sense cheaper).
Worried about shielding... bring lots of water. You'll need it anyway.
Water is cheap. Upmass isn't but it's getting cheaper.
Worried about breakdowns, bring redundancy and quantify the risk. At some
point you're going to have to kick the tires, light the engines and go
anyway.
Look, SpaceX launch prices are about $4K/kg to LEO. That's not cheap but
getting there. And that's their list price. I bet their costs are lower
and dropping.
If I did my math right and am stealing numbers from NASA's 2007 reference
mission, they want about 400mt to LEO.
So, 400,000*4,000 and I get $1.6B.
I'll double that since I'm conservative.
That's getting to the point where it's relatively cheap.
(give SpaceX a decade to get launch costs down another 50% and then we'll
see private folks doing it!)
>
--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
Jeff Findley
May 16, 2013, 4:16:34 PM5/16/13
to
In article <45f119c9-099b-4519-87cc-
c69bea...@z8g2000yqd.googlegroups.com>, hal...@aol.com says...
>
> On May 16, 9:26ï¿œam, Jeff Findley <jeff.find...@nospam.ugs.com> wrote:
> >
> > B.S. ï¿œChemical propulsion is all that is needed. ï¿œAppropriate engines
> a 3 year mission to mars isnt doable/
You're not an expert in the domain of aerospace engineering. You have
no idea what's "doable" or not. Anyone who claims that 3 year missions
aren't "doable" either don't know what they're talking about, or they're
lying in order to get funding for *their* pet research project (e.g.
nuclear rocket engines).
> flags and footprints is a dead end think apollo.
We got "flags and footprints" because it was the *fastest* way to beat
the Russians to the moon and because the mantra at the time was "waste
anything but time", and that certainly included money. Beating those
"Godless Commies" to the moon came first. Doing something useful while
on the surface of the moon was an afterthought.
The Apollo/Saturn program ended precisely because it was *too expensive*
to maintain. Get that through your thick skull, will you?
> the only practical one is nuke booster of some type to cut travel time
> dramatically
"Practical" and "nuke booster" do not belong in the same sentence!
c69bea...@z8g2000yqd.googlegroups.com>, hal...@aol.com says...
>
> On May 16, 9:26ï¿œam, Jeff Findley <jeff.find...@nospam.ugs.com> wrote:
> >
> > B.S. ï¿œChemical propulsion is all that is needed. ï¿œAppropriate engines
> > either exist or are currently under development for such a task.
> >
> > VASMIR isn't ready for such a big mission (in terms of mass to deliver
> > to Mars). ï¿œWhere do you get the *enormous* amount of electrical power
> >
> > VASMIR isn't ready for such a big mission (in terms of mass to deliver
> > needed to run VASMIR engines of sufficient thrust for a manned Mars
> > mission? ï¿œNuclear? ï¿œAnd this is supposed to save money? ï¿œThat would be
> > insanity on the level of Bob Haller.
> >
> > There is no magic propulsion technology which will make going to Mars
> > *cheaper*.
>
> >
> > There is no magic propulsion technology which will make going to Mars
> > *cheaper*.
>
> dont think cheap think possible.
If it's not cheap enough to be funded, it's not possible.
> a 3 year mission to mars isnt doable/
no idea what's "doable" or not. Anyone who claims that 3 year missions
aren't "doable" either don't know what they're talking about, or they're
lying in order to get funding for *their* pet research project (e.g.
nuclear rocket engines).
> flags and footprints is a dead end think apollo.
the Russians to the moon and because the mantra at the time was "waste
anything but time", and that certainly included money. Beating those
"Godless Commies" to the moon came first. Doing something useful while
on the surface of the moon was an afterthought.
The Apollo/Saturn program ended precisely because it was *too expensive*
to maintain. Get that through your thick skull, will you?
> the only practical one is nuke booster of some type to cut travel time
> dramatically
Jeff Findley
May 16, 2013, 4:21:15 PM5/16/13
to
In article <vemdnajvx47XvgjM...@earthlink.com>,
moo...@ignorethisgreenms.com says...
Something like a Falcon Heavy with reusable boosters and a reusable,
core, first stage ought to do the trick. Even with an expendable upper
stage, that would be reusing 27 Merlin engines and throwing away only
one.
moo...@ignorethisgreenms.com says...
core, first stage ought to do the trick. Even with an expendable upper
stage, that would be reusing 27 Merlin engines and throwing away only
one.
bob haller
May 16, 2013, 6:11:40 PM5/16/13
to
from the link......
For comparison, past NASA studies have centered on Mars flights that
would take two years to complete, and could cost $12 billion just to
launch the fuel needed for the mission, according to Slough's team.
with government cutting entitlments, cuttin social security medicare
and everything else, 12 billion just to pay to launch fuel is
politically as dead as the shuttle flying again.......
For comparison, past NASA studies have centered on Mars flights that
would take two years to complete, and could cost $12 billion just to
launch the fuel needed for the mission, according to Slough's team.
and everything else, 12 billion just to pay to launch fuel is
politically as dead as the shuttle flying again.......
bob haller
May 17, 2013, 8:33:17 AM5/17/13
to
> The Apollo/Saturn program ended precisely because it was *too expensive*
> to maintain. Get that through your thick skull, will you?
>
> > the only practical one is nuke booster of some type to cut travel time
> > dramatically
>
jeff note saturn was replaced by shuttle which cost even more and
lacked heavy lift.... besides lacking launch boost escape......
6 months each way appears to be the shortest number of months to mars,
and would allow very little mars ground time, perhaps a week or two.
so the mars mission would be around 3 years.
for a nuke power mission transit time 2 months each way, with perhaps
2 months mars ground time....
thats affordable once the nuke booster stage is built, and it could be
reused after return from mars..
a 3 year mission with a tether, carrying everything that might break
at any time during the entire trip is just not practical.....
Jeff Findley
May 17, 2013, 8:49:47 AM5/17/13
to
In article <94cb76d3-9b1c-4947-a2a2-9c538477dbd7
@z10g2000yqd.googlegroups.com>, hal...@aol.com says...
Launch costs will continue to go down as companies like SpaceX pursue
reusable launch vehicles. Throwing away launch vehicles on every flight
is a huge problem that will hopefully be rectified in the next 10 years
or so. Once that's accomplished, NASA can contract for delivery of fuel
to LEO on these cheaper vehicles, even if they still think they "need"
to launch the hardware on SLS.
Note that fuel and oxidizer does not require a HLV of any kind since
it's a payload that's almost infinitely divisible into smaller pieces.
A smallish, reusable, launch vehicle flying at a high flight rate might
just be the solution needed here. With no hard requirement for a
certain payload for a reusable delivering fuel and oxidizer, arguments
that reusability will eat into payload fall flat, as long as the cost
per pound to LEO is smaller than today's launch costs and as long as the
flight rate can be ramped up high enough to deliver the amount of fuel
and oxidizer required in a timely manner.
> with government cutting entitlments, cuttin social security medicare
> and everything else, 12 billion just to pay to launch fuel is
> politically as dead as the shuttle flying again.......
Perhaps that's true today, but I doubt that will be the case in 10
years.
@z10g2000yqd.googlegroups.com>, hal...@aol.com says...
>
> from the link......
>
> For comparison, past NASA studies have centered on Mars flights that
> would take two years to complete, and could cost $12 billion just to
> launch the fuel needed for the mission, according to Slough's team.
But what assumptions were made about launch costs?
> from the link......
>
> For comparison, past NASA studies have centered on Mars flights that
> would take two years to complete, and could cost $12 billion just to
> launch the fuel needed for the mission, according to Slough's team.
Launch costs will continue to go down as companies like SpaceX pursue
reusable launch vehicles. Throwing away launch vehicles on every flight
is a huge problem that will hopefully be rectified in the next 10 years
or so. Once that's accomplished, NASA can contract for delivery of fuel
to LEO on these cheaper vehicles, even if they still think they "need"
to launch the hardware on SLS.
Note that fuel and oxidizer does not require a HLV of any kind since
it's a payload that's almost infinitely divisible into smaller pieces.
A smallish, reusable, launch vehicle flying at a high flight rate might
just be the solution needed here. With no hard requirement for a
certain payload for a reusable delivering fuel and oxidizer, arguments
that reusability will eat into payload fall flat, as long as the cost
per pound to LEO is smaller than today's launch costs and as long as the
flight rate can be ramped up high enough to deliver the amount of fuel
and oxidizer required in a timely manner.
> with government cutting entitlments, cuttin social security medicare
> and everything else, 12 billion just to pay to launch fuel is
> politically as dead as the shuttle flying again.......
years.
Jeff Findley
May 17, 2013, 9:17:40 AM5/17/13
to
In article <7417a241-08f1-429b-85dd-ab90360c91b3
@r3g2000yqe.googlegroups.com>, hal...@aol.com says...
is that shuttle was still cheaper, so its funding continued.
> 6 months each way appears to be the shortest number of months to mars,
> and would allow very little mars ground time, perhaps a week or two.
>
> so the mars mission would be around 3 years.
>
> for a nuke power mission transit time 2 months each way, with perhaps
> 2 months mars ground time....
Where are you getting these numbers? Cite?
> thats affordable once the nuke booster stage is built, and it could be
> reused after return from mars..
>
> a 3 year mission with a tether, carrying everything that might break
> at any time during the entire trip is just not practical.....
You're not an engineer or an accountant, so why should be believe your
"feeling" based analysis of what you think is affordable?
@r3g2000yqe.googlegroups.com>, hal...@aol.com says...
>
> > The Apollo/Saturn program ended precisely because it was *too expensive*
> > to maintain. ï¿œGet that through your thick skull, will you?
> > The Apollo/Saturn program ended precisely because it was *too expensive*
> >
> > > the only practical one is nuke booster of some type to cut travel time
> > > dramatically
>
> >
> > Jeff
>
> jeff note saturn was replaced by shuttle which cost even more and
> lacked heavy lift.... besides lacking launch boost escape......
Irrelevant when the decision was made to cancel Apollo/Saturn. The fact
> > > the only practical one is nuke booster of some type to cut travel time
> > > dramatically
>
> >
> > Jeff
>
> jeff note saturn was replaced by shuttle which cost even more and
> lacked heavy lift.... besides lacking launch boost escape......
is that shuttle was still cheaper, so its funding continued.
> 6 months each way appears to be the shortest number of months to mars,
> and would allow very little mars ground time, perhaps a week or two.
>
> so the mars mission would be around 3 years.
>
> for a nuke power mission transit time 2 months each way, with perhaps
> 2 months mars ground time....
> thats affordable once the nuke booster stage is built, and it could be
> reused after return from mars..
>
> a 3 year mission with a tether, carrying everything that might break
> at any time during the entire trip is just not practical.....
"feeling" based analysis of what you think is affordable?
bob haller
May 17, 2013, 3:01:29 PM5/17/13
to
On May 17, 9:17 am, Jeff Findley <jeff.find...@nospam.ugs.com> wrote:
> In article <7417a241-08f1-429b-85dd-ab90360c91b3
> @r3g2000yqe.googlegroups.com>, hall...@aol.com says...
> In article <7417a241-08f1-429b-85dd-ab90360c91b3
>
>
>
> > > The Apollo/Saturn program ended precisely because it was *too expensive*
> > > to maintain. Get that through your thick skull, will you?
>
>
> > > The Apollo/Saturn program ended precisely because it was *too expensive*
least 6 months
nuke booster is supposed to shorten that to about 2 months
now 6 months each way is a year in transit. and unless its only a
flag and footprints mission you need a year or more ground time on
mars. to get closer to conjunction more than a year.
earth mars with decent time on mars makes it roughly a 3 year
mission...... one that requires taking everything you need for 3 years
from earth
Message has been deleted
Message has been deleted
Message has been deleted
bob haller
May 18, 2013, 6:11:00 PM5/18/13
to
bob haller
May 18, 2013, 6:17:19 PM5/18/13
to
On May 18, 6:11 pm, bob haller <hall...@aol.com> wrote:
> http://abclocal.go.com/ktrk/story?section=news/local&id=9105418
HOUSTON (KTRK) -- The budget fight in Washington is hitting the space
program. NASA says thanks to the sequester, its goals of future space
travel may be put on hold.
NASA is trying to make plans amid the sequester and budget
uncertainty. It's no easy task, but NASA administrator Charles Bolden
says the space agency's three priorities right now are clear.
Every day for the last 13 years, a NASA astronaut has been working
aboard the International Space Station. Bolden calls it and the
research conducted there the "springboard" which will lead us into the
next phase of exploration.
Getting there alone is a challege still, as no commerical company yet
has developed a vehicle for us to get our astronauts into space.
Bolden just authorized spending over $450 million through 2017 for us
to keep hitching a ride there with the Russians.
"Thats the last check I want to write to somebody outside the United
States," Bolden said.
The next priority is figuring out a way to get to a near-Earth
asteroid. But the ultimate goal, by sometime in the 2030s, is to have
humans exploring Mars.
All that costs money, and Bolden says NASA's $16.8 billion budget
request gets chopped to just $16.1 billion if the seqester is not
rectified.
"At the $16.1 billion level, there is no way in the world they can
continue to operate a center like JSC at the level of employment that
we have right now," Bolden said.
Bolden laments this would mean cutbacks at all NASA centers, primarily
contractors. But furloughs for civil servants, he confides, could also
become necessary.
"What we're focused on is what can we get done with the money that we
have so that we are continuing to move forward in space," Johnson
Space Center Director Dr. Ellen Ochoa said.
Moving forward has always been NASA's goal. If we can get humans to
Mars, maybe one day we can live there -- just in case something
cataclysmic happens back home.
"A critical question we have to answer for the world, is can we save
the planet if necessary?" Bolden said.
One thing they're working on here is the propulsion systems that would
get us to Mars. They've figured out that there is no way to get there
using chemical rockets like we have now. Bolden says they are trying
to develop solar-electric propulsion. The trick is apparently figuring
out how to do it on a scale large enough, strong enough, to do the
job, of getting us to Mars.
------------------------------------------------------------------
lets see budget cuts hurting , no way for chemical propulsion to get
us to mars........
where have i heard that before?
> http://abclocal.go.com/ktrk/story?section=news/local&id=9105418
HOUSTON (KTRK) -- The budget fight in Washington is hitting the space
program. NASA says thanks to the sequester, its goals of future space
travel may be put on hold.
NASA is trying to make plans amid the sequester and budget
uncertainty. It's no easy task, but NASA administrator Charles Bolden
says the space agency's three priorities right now are clear.
Every day for the last 13 years, a NASA astronaut has been working
aboard the International Space Station. Bolden calls it and the
research conducted there the "springboard" which will lead us into the
next phase of exploration.
Getting there alone is a challege still, as no commerical company yet
has developed a vehicle for us to get our astronauts into space.
Bolden just authorized spending over $450 million through 2017 for us
to keep hitching a ride there with the Russians.
"Thats the last check I want to write to somebody outside the United
States," Bolden said.
The next priority is figuring out a way to get to a near-Earth
asteroid. But the ultimate goal, by sometime in the 2030s, is to have
humans exploring Mars.
All that costs money, and Bolden says NASA's $16.8 billion budget
request gets chopped to just $16.1 billion if the seqester is not
rectified.
"At the $16.1 billion level, there is no way in the world they can
continue to operate a center like JSC at the level of employment that
we have right now," Bolden said.
Bolden laments this would mean cutbacks at all NASA centers, primarily
contractors. But furloughs for civil servants, he confides, could also
become necessary.
"What we're focused on is what can we get done with the money that we
have so that we are continuing to move forward in space," Johnson
Space Center Director Dr. Ellen Ochoa said.
Moving forward has always been NASA's goal. If we can get humans to
Mars, maybe one day we can live there -- just in case something
cataclysmic happens back home.
"A critical question we have to answer for the world, is can we save
the planet if necessary?" Bolden said.
One thing they're working on here is the propulsion systems that would
get us to Mars. They've figured out that there is no way to get there
using chemical rockets like we have now. Bolden says they are trying
to develop solar-electric propulsion. The trick is apparently figuring
out how to do it on a scale large enough, strong enough, to do the
job, of getting us to Mars.
------------------------------------------------------------------
lets see budget cuts hurting , no way for chemical propulsion to get
us to mars........
where have i heard that before?
Message has been deleted
Message has been deleted
Wrong Stuff
May 19, 2013, 2:58:11 AM5/19/13
to
Only fire it off from lunar orbit and then only return to lunar orbit
after the trip.
Is the priority getting to Mars or is it to develop a system that
can meaningfully extend the reach of humanity to Mars and beyond?
Faster seems vastly better even if it takes considerably more
development time.
Perhaps Mars should be explored by robotics controlled by humans
in orbit that operate control gloves and joysticks. Perhaps from
based of the moons of Mars for radiation protection. With sleep in
a centrifuge to reproduce normal gravity.
Finally should we assume the deeper gravity wells are the best goal?
Perhaps the ideal is a huge ship the processes the smaller bodies found
in space for resources. Granted that is a far term goal but then it
all is just that, IMO.
bob haller
May 19, 2013, 9:16:44 AM5/19/13
to
currently and for the foresable future theres no money for a big grand
manned mars mission because of the current world economy. it makes
much better sense to repurpose the bucks being wasted on orion for the
nuke stage that can be used for mars and beyond......
just accept that mars missions will be launched in pieces and
assembled in orbit, by private industry....
this is likely the most economical approach.
manned mars mission because of the current world economy. it makes
much better sense to repurpose the bucks being wasted on orion for the
nuke stage that can be used for mars and beyond......
just accept that mars missions will be launched in pieces and
assembled in orbit, by private industry....
this is likely the most economical approach.
Wrong Stuff
May 19, 2013, 12:26:22 PM5/19/13
to
be unmanned, slow-boat, choice making, robotic explorers. Already,
there are predictions of the replacement of much of lower level
labor by robotic workers. Nor should even higher level worker
such as geologists think they can't largely be replaced by
solid robotics with good algorithmic decision tree.
Perhaps the most pressing thing is what to do with all us
extras or the next several decades? Feed us more bis-phenol-A and Round-up ready soy?
It seems we are terraforming Greenland to be green...........Trig
bob haller
May 19, 2013, 1:23:37 PM5/19/13
to
at some point the world economy must change when people will no longer
have to work to support themselves
Message has been deleted
Wrong Stuff
May 19, 2013, 4:31:40 PM5/19/13
to
On Sunday, May 19, 2013 10:28:02 AM UTC-7, Fred J. McCall wrote:
Yes, I hoping this is an easier bar to jump for the big jump. I am not
too worried about a few fission products sent out the back end.
>
>
>
> >
>
> >Is the priority getting to Mars or is it to develop a system that
>
> >can meaningfully extend the reach of humanity to Mars and beyond?
>
> >Faster seems vastly better even if it takes considerably more
>
> >development time.
>
> >
>
>
>
> No need to wait for the perfect transportation system to start going
>
> places. They're not mutually exclusive paths. Waiting until you have
>
> the 'perfect' system means you will never go anywhere.
>
I agree there a need of multiple paths.
>
> >
>
> >Perhaps Mars should be explored by robotics controlled by humans
>
> >in orbit that operate control gloves and joysticks. Perhaps from
>
> >based of the moons of Mars for radiation protection. With sleep in
>
> >a centrifuge to reproduce normal gravity.
>
> >
>
>
>
> Once you bring the humans all that way, it makes more sense to land
>
> them and do actual exploration. People are a couple of orders more
>
> productive than unmanned toasters.
I've a couple of thoughts here and I repeating myself to an extent.
The "unmanned toasters" are subject to Moore's law so they should
reach a threshold of function that makes them more useful. Today
isn't tomorrow so to speak.
And second if people are in orbit, the toasters can effectively be
manned as the lag time is greatly reduced. Imagine a human form robot controlled from a station located on Deimos. This is tech that merits Earth bound jobs and thus should be funded and improved for here as well as the surface of Mars. Yes, I recycling one NASA's arguments for funding.
Sure, people on the surface or in tunnels in time. Depending. Then again
Mars might be great gravity well to toss the 'country rocks' generated when
its moons are processed for human uses. As there is always one of those 'damned' enviro-dark-siders (mixed multiple reference) wanting a clean orbital environment.
>
>
>
> >
>
> >Finally should we assume the deeper gravity wells are the best goal?
>
> >Perhaps the ideal is a huge ship the processes the smaller bodies found
>
> >in space for resources. Granted that is a far term goal but then it
>
> >all is just that, IMO.
>
> >
>
>
>
> If we want to get a space based civilization, we need to build it by
>
> processing space based resources. Lifting stuff out of gravity wells
>
> is too expensive. This is something of a chicken and egg problem.
I fully agree. I am more excited by asteroids than most. Also why
I suspect in a more final form, spacecraft will be more like an
an aircraft carriers (or Pepsi bottling plants) than a Pepsi cans.
hoping to lob eggs into space and get them to hatch................Trig
>
>
>
> --
>
> "The reasonable man adapts himself to the world; the unreasonable
>
> man persists in trying to adapt the world to himself. Therefore,
>
> all progress depends on the unreasonable man."
>
> --George Bernard Shaw
> Wrong Stuff <trigonom...@gmail.com> wrote:
>
>
>
> >On Wednesday, May 15, 2013 10:03:10 AM UTC-7, Jeff Findley wrote:
>
> >> In article <1e70aa6d-612a-4dad-8d4d-
>
> >>
>
> >>
>
>
>
>
> >On Wednesday, May 15, 2013 10:03:10 AM UTC-7, Jeff Findley wrote:
>
> >> In article <1e70aa6d-612a-4dad-8d4d-
>
> >>
>
> >>
>
> >> Seriously though, we know how to make and store spare parts, food, and
>
> >> water. We know how to increase the delta-V of chemical stages (add more
>
> >> fuel and oxidizer tanks and drop them when empty). We don't quite know
>
> >> how to make a safe nuclear rocket engine.
>
> >>
>
> >
>
>
> >> water. We know how to increase the delta-V of chemical stages (add more
>
> >> fuel and oxidizer tanks and drop them when empty). We don't quite know
>
> >> how to make a safe nuclear rocket engine.
>
> >>
>
> >
>
> >Perhaps we should make an "unsafe" one and deal with it.
>
> >Only fire it off from lunar orbit and then only return to lunar orbit
>
> >after the trip.
>
> >
>
>
>
> There's still the whole "safe for the people riding it" thing.
>
> >Only fire it off from lunar orbit and then only return to lunar orbit
>
> >after the trip.
>
> >
>
>
>
Yes, I hoping this is an easier bar to jump for the big jump. I am not
too worried about a few fission products sent out the back end.
>
>
>
> >
>
> >Is the priority getting to Mars or is it to develop a system that
>
> >can meaningfully extend the reach of humanity to Mars and beyond?
>
> >Faster seems vastly better even if it takes considerably more
>
> >development time.
>
> >
>
>
>
>
> places. They're not mutually exclusive paths. Waiting until you have
>
> the 'perfect' system means you will never go anywhere.
>
I agree there a need of multiple paths.
>
> >
>
> >Perhaps Mars should be explored by robotics controlled by humans
>
> >in orbit that operate control gloves and joysticks. Perhaps from
>
> >based of the moons of Mars for radiation protection. With sleep in
>
> >a centrifuge to reproduce normal gravity.
>
> >
>
>
>
>
> them and do actual exploration. People are a couple of orders more
>
> productive than unmanned toasters.
I've a couple of thoughts here and I repeating myself to an extent.
The "unmanned toasters" are subject to Moore's law so they should
reach a threshold of function that makes them more useful. Today
isn't tomorrow so to speak.
And second if people are in orbit, the toasters can effectively be
manned as the lag time is greatly reduced. Imagine a human form robot controlled from a station located on Deimos. This is tech that merits Earth bound jobs and thus should be funded and improved for here as well as the surface of Mars. Yes, I recycling one NASA's arguments for funding.
Sure, people on the surface or in tunnels in time. Depending. Then again
Mars might be great gravity well to toss the 'country rocks' generated when
its moons are processed for human uses. As there is always one of those 'damned' enviro-dark-siders (mixed multiple reference) wanting a clean orbital environment.
>
>
>
> >
>
> >Finally should we assume the deeper gravity wells are the best goal?
>
> >Perhaps the ideal is a huge ship the processes the smaller bodies found
>
> >in space for resources. Granted that is a far term goal but then it
>
> >all is just that, IMO.
>
> >
>
>
>
>
> processing space based resources. Lifting stuff out of gravity wells
>
> is too expensive. This is something of a chicken and egg problem.
I fully agree. I am more excited by asteroids than most. Also why
I suspect in a more final form, spacecraft will be more like an
an aircraft carriers (or Pepsi bottling plants) than a Pepsi cans.
hoping to lob eggs into space and get them to hatch................Trig
>
>
>
> --
>
> "The reasonable man adapts himself to the world; the unreasonable
>
> man persists in trying to adapt the world to himself. Therefore,
>
> all progress depends on the unreasonable man."
>
> --George Bernard Shaw
Message has been deleted
0 new messages