Remember the Ranger probes? 6 failures in a row....
Jens Lerch
>>Well, Mars Pathfinder, Cassini, Deep Space 1, Lunar Prospector,
>>to name a few, argue that it can be done. And we don't even know that
>>the failure is attributable to "faster, better, cheaper." Remember
>>that the last major Mars mission before "faster, better, cheaper,"
>>the $1 billion Mars Observer, was also lost without a trace. Sometimes
>>things are just going to go wrong. After all, this *is* rocket science.
>First drop Cassini. It's the last of the "BIG$" missions.
>That leaves Pathfinder, Deep Space and Prospector as successful. Climate
>Orbiter and
>Polar Lander as failures. I don't think three out of five is very good. If you
>separate the Deep Space 2 probes your down to 50%
You forgot NEAR (Discovery 1) which failed to rendevouz with Eros last
December, but it will get a second chance on next Valentine's Day, so it
could still become an almost complete success.
And Stardust (Discovery 4) was launched early this year. It is currently
collecting particles of the solar wind, while being on target to fly
through the coma of a comet to collect dust for return to Earth.
In the last 4 years the track record of interplanetary FBC probes has
been:
Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
Failure: Mars Climate Orbiter, Mars Polar Lander, Deep Space 2
Pending: NEAR, Stardust
Since 1980 the rather short track record of the big budget
interplanetary missions has been:
Success: Magellan, Galileo
Failure: Mars Observer
Pending: Cassini
Within the accuracy possible by the small sample size the reliability of
FBC and big budget probes is the same, but due to FBC more probes are
launched now per year than formerly in an entire decade.
--
"Space travel is utter bilge." | Jens Lerch
Richard van der Riet Wooley, | jle...@geocities.com
British Astronomer Royal, 1956 | http://jens.lerch.home.pages.de/
rk
> dc...@aol.comnospam (Darren C. Bly) wrote:
>
> >>Well, Mars Pathfinder, Cassini, Deep Space 1, Lunar Prospector,
> >>to name a few, argue that it can be done. And we don't even know that
> >>the failure is attributable to "faster, better, cheaper." Remember
> >>that the last major Mars mission before "faster, better, cheaper,"
> >>the $1 billion Mars Observer, was also lost without a trace. Sometimes
> >>things are just going to go wrong. After all, this *is* rocket science.
>
> >First drop Cassini. It's the last of the "BIG$" missions.
>
> >That leaves Pathfinder, Deep Space and Prospector as successful. Climate Orbiter
> and
> >Polar Lander as failures. I don't think three out of five is very good. If you
> >separate the Deep Space 2 probes your down to 50%
>
> You forgot NEAR (Discovery 1) which failed to rendevouz with Eros last
> December, but it will get a second chance on next Valentine's Day, so it
> could still become an almost complete success.
> And Stardust (Discovery 4) was launched early this year. It is currently
> collecting particles of the solar wind, while being on target to fly
> through the coma of a comet to collect dust for return to Earth.
>
> In the last 4 years the track record of interplanetary FBC probes has
> been:
>
> Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
> Failure: Mars Climate Orbiter, Mars Polar Lander, Deep Space 2
> Pending: NEAR, Stardust
first, m. pathfinder had a lot of "investment" from mars explorer; if you add that
in, does it really count as "fbc?" perhaps it's a small mars explorer?
secondly, perhaps we can include clementine, which seemed to have "fbc" attributes.
================================
> Since 1980 the rather short track record of the big budget
> interplanetary missions has been:
>
> Success: Magellan, Galileo
> Failure: Mars Observer
> Pending: Cassini
you can increase the sample size by going back two more years, where we had pioneer
venus 1 and 2 (with probes). moving back some more, we get voyager (1, 2) and
{viking (1, 2) each with a lander}.
==================================
> Within the accuracy possible by the small sample size the reliability of
> FBC and big budget probes is the same, but due to FBC more probes are
> launched now per year than formerly in an entire decade.
of course, i am a big fan and supporter of "fbc."
it's tough to classify spacecraft as "fbc" or not "fbc". faster and cheaper is
easier, but how do we define "better?"
------------------------------------------------------------------------
rk The world of space holds vast promise
stellar engineering, ltd. for the service of man, and it is a
stel...@erols.com.NOSPAM world we have only begun to explore.
Hi-Rel Digital Systems Design -- James E. Webb, 1968
George Herbert
>You forgot NEAR (Discovery 1) which failed to rendevouz with Eros last
>December, but it will get a second chance on next Valentine's Day, so it
>could still become an almost complete success.
>And Stardust (Discovery 4) was launched early this year. It is currently
>collecting particles of the solar wind, while being on target to fly
>through the coma of a comet to collect dust for return to Earth.
>
>In the last 4 years the track record of interplanetary FBC probes has
>been:
>
>Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
>Failure: Mars Climate Orbiter, Mars Polar Lander, Deep Space 2
>Pending: NEAR, Stardust
I personally would take DS2 off the list; it wasn't a completely
seperate mission, it was a subpayload and should be counted as
a MPL experiment. The failure that got MPL probably got DS2
as well.
>Since 1980 the rather short track record of the big budget
>interplanetary missions has been:
>
>Success: Magellan, Galileo
>Failure: Mars Observer
>Pending: Cassini
Galileo was only around 2/3 successful. If you count experiment
time at place and key imaging, it's over 90% successful, but the
limitations and overall data loss due to the antenna got a good
chunk of its mission objective data return.
>Within the accuracy possible by the small sample size the reliability of
>FBC and big budget probes is the same, but due to FBC more probes are
>launched now per year than formerly in an entire decade.
Good point.
-george william herbert
gher...@crl.com
Brian Thorn
wrote:
>Success: Magellan, Galileo
And Ulysses. But Galileo is a very qualified success. 10% of planned
data collected looks great compared to MPL and MCO, but that's
definitely not good by any other measure.
rk
> On Fri, 10 Dec 1999 22:52:46 GMT, jle...@geocities.com (Jens Lerch)
> wrote:
>
> >Success: Magellan, Galileo
>
> And Ulysses. But Galileo is a very qualified success. 10% of planned
> data collected looks great compared to MPL and MCO, but that's
> definitely not good by any other measure.
i would most definitely use another measure; typically, for these sorts
of missions, they have science requirements which must be met and goals
which is desired to be met. this is distinctly different than the amount
of data downloaded. while the mission is more expensive than planned
(reprogramming computers for data compression, etc.) and there will be
less data than planned, i wouldn't be tempted to say that the success of
the mission is in direct proportion to the amount of data downloaded; a
comparison needs to be made of science goals met vs. required. i also
note that the spacecraft has returned data from extended periods of
operations.
since we have a scientist that does galileo analysis on the newsgroup,
i'll shut up now and perhaps he'll chime in. :-)
have a good evening,
Tom Abbott
wrote:
>dc...@aol.comnospam (Darren C. Bly) wrote:
>
>>>Well, Mars Pathfinder, Cassini, Deep Space 1, Lunar Prospector,
>>>to name a few, argue that it can be done. And we don't even know that
>>>the failure is attributable to "faster, better, cheaper." Remember
>>>that the last major Mars mission before "faster, better, cheaper,"
>>>the $1 billion Mars Observer, was also lost without a trace. Sometimes
>>>things are just going to go wrong. After all, this *is* rocket science.
>
>>First drop Cassini. It's the last of the "BIG$" missions.
>
>>That leaves Pathfinder, Deep Space and Prospector as successful. Climate
>>Orbiter and
>>Polar Lander as failures. I don't think three out of five is very good. If you
>>separate the Deep Space 2 probes your down to 50%
>
>You forgot NEAR (Discovery 1) which failed to rendevouz with Eros last
>December, but it will get a second chance on next Valentine's Day, so it
>could still become an almost complete success.
>And Stardust (Discovery 4) was launched early this year. It is currently
>collecting particles of the solar wind, while being on target to fly
>through the coma of a comet to collect dust for return to Earth.
>
>In the last 4 years the track record of interplanetary FBC probes has
>been:
>
>Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
>Failure: Mars Climate Orbiter, Mars Polar Lander, Deep Space 2
>Pending: NEAR, Stardust
>
>Since 1980 the rather short track record of the big budget
>interplanetary missions has been:
>
>Success: Magellan, Galileo
>Failure: Mars Observer
>Pending: Cassini
>
>Within the accuracy possible by the small sample size the reliability of
>FBC and big budget probes is the same, but due to FBC more probes are
>launched now per year than formerly in an entire decade.
And we seem to be getting more scientific data about the solar
system and beyond from the "BattleStar Gallactica" space probes and
satellites like Hubble and Galileo, than from the smaller, faster
probes.
TA
Henry Spencer
Tom Abbott <tab...@intellex.com> wrote:
> And we seem to be getting more scientific data about the solar
>system and beyond from the "BattleStar Gallactica" space probes and
>satellites like Hubble and Galileo, than from the smaller, faster
>probes.
Nobody's ever disputed that you get more science return from a Battlestar
class probe... if it works. The problem is that they are too expensive to
be launched very often -- pretty nearly too expensive to be launched at
all, any more -- and also it puts far too many eggs in one basket.
How much scientific data about the Moon or Mars have we gotten from
Battlestar-class probes in the last twenty years?
--
The space program reminds me | Henry Spencer he...@spsystems.net
of a government agency. -Jim Baen | (aka he...@zoo.toronto.edu)
Tom Abbott
wrote:
>In article <mbdSOOoc8d07HH...@4ax.com>,
>Tom Abbott <tab...@intellex.com> wrote:
>> And we seem to be getting more scientific data about the solar
>>system and beyond from the "BattleStar Gallactica" space probes and
>>satellites like Hubble and Galileo, than from the smaller, faster
>>probes.
>
>Nobody's ever disputed that you get more science return from a Battlestar
>class probe... if it works. The problem is that they are too expensive to
>be launched very often -- pretty nearly too expensive to be launched at
>all, any more -- and also it puts far too many eggs in one basket.
>
>How much scientific data about the Moon or Mars have we gotten from
>Battlestar-class probes in the last twenty years?
Well, we've gotten qute a bit of data actually, as some of them fly
past the Moon for other destinations. No doubt if we had put a
Hubble-type telescope to orbiting the Moon, we would know a whole lot
more about the Moon than we do now.
TA
Frank Crary
rk <stel...@NOSPAM.erols.com> wrote:
>> And Ulysses. But Galileo is a very qualified success. 10% of planned
>> data collected looks great compared to MPL and MCO, but that's
>> definitely not good by any other measure.
>i would most definitely use another measure; typically, for these sorts
>of missions, they have science requirements which must be met and goals
>which is desired to be met. this is distinctly different than the amount
>of data downloaded. while the mission is more expensive than planned
>(reprogramming computers for data compression, etc.) and there will be
>less data than planned, i wouldn't be tempted to say that the success of
>the mission is in direct proportion to the amount of data downloaded; a
>comparison needs to be made of science goals met vs. required. i also
>note that the spacecraft has returned data from extended periods of
>operations.
>since we have a scientist that does galileo analysis on the newsgroup,
>i'll shut up now and perhaps he'll chime in. :-)
I'm not sure if I want to. I agree with everything you said, but I'm
also unwilling to attach a percent to how successful a mission is.
JPL and NASA say that Galileo accomplished 80% of its science goals,
and they got that number (as I understand it) by going through the list
of science goals, giving each a yes/no value, and dividing the number
of yes's by the number of items. Usually, it isn't that simple. There
is, ``yes, but not as well as we wanted'',``definitely yes, but we
could have done better'', ``no but we still got some good data along
those lines'', etc. Nor were all the goals of equal value, although
you could argue endlessly about which were worth more than others.
Then you get into the never-never land of things that were not on that
list. I'm fairly sure that magnetometer data on the existence of an
ocean on Europa wasn't on the list, and I'm quite sure that similar
data on an ocean within Callisto definitely wasn't (just to use one
example I'm familiar with.) Often, when you observe something, you
discover something you did not expect to find. In several cases, Galileo
has done that. Would there have been more unexpected discoveries if
the high gain antenna had opened? Yes, definitely. But how many and
how important? How can you attach a number to something like that?
I would say that Galileo is a success, but not a complete success,
and that the sum total of the scientific results is between 50 and
100% of what it might have achieved. I don't know, and I don't even
know how to figure out, where between 50 and 100% the ``real'' value
is.
Frank Crary
CU Boulder
rk
getting back to the original poster, stating "10% of planned data collected
looks great compared to MPL and MCO" sort of implies 10% of the mission
goals. for some missions, that may be true, if the requirements were
something like, "image 80% of the planet with 100 meter resolution" and only
8% was done. from some missions i have seen hard science requirements + goals
listed ... and i stated previously, per cent complete can be higher than data
wanted. i don't know how to factor in the extended missions, but they'll add
to the science return, too.
looking at things financially, if we did get only 10% of the goals, than we
got (rounding) about $100K worth of science ... less then then cost of a
discovery spacecraft (or is that mission) and slightly more than a small
explorer. while i can't interpret the science at all, i believe from what
i've read and what you posted the mission was considerably more successful
than that.
om
wrote:
>How much scientific data about the Moon or Mars have we gotten from
>Battlestar-class probes in the last twenty years?
...Henry, old pal, that's a partially loaded question. There haven't
been *any* Ponderosa-class probes to the moon in the past 20 years,
and even during the heydays there weren't any launched with the
heavy-duty size and configuration along the lines of Cassini or even
Viking. Surveyor was probably the closest we've come sending such.
OM
Henry Spencer
Tom Abbott <tab...@intellex.com> wrote:
>>How much scientific data about the Moon or Mars have we gotten from
>>Battlestar-class probes in the last twenty years?
>
>past the Moon for other destinations.
"Some"? I count one. (Cassini made no significant lunar observations,
last I heard.) And the Galileo observations, while of some interest,
are minor footnotes compared to what Clementine and Lunar Prospector --
missions which *together* cost literally an order of magnitude less --
yielded.
>No doubt if we had put a
>Hubble-type telescope to orbiting the Moon, we would know a whole lot
>more about the Moon than we do now.
Oh, undoubtedly. And if there were exploring parties setting out from
Luna City twice a week, we'd know still more. But neither of those "ifs"
has anything to do with the real world. Like I said, nobody disputes that
Battlestar missions are better, other things being equal... but other
things are *NOT* equal, and a flying F/B/C is lots better than a cancelled
Battlestar. And that is the choice.
Henry Spencer
om <om@REMOVE_THIS.ccsi.com> wrote:
>>How much scientific data about the Moon or Mars have we gotten from
>>Battlestar-class probes in the last twenty years?
>
Yep, quite true. And there's a reason for that, and it's not that there's
no interesting lunar science left to do. (There was one *planned* --
Lunar Observer, the second in the Observer series -- but it died with the
truncation of Observer.) Battlestar-class missions are hard to fund.
>and even during the heydays there weren't any launched with the
>heavy-duty size and configuration along the lines of Cassini or even
>Viking. Surveyor was probably the closest we've come sending such.
The early Rangers were, *for their day*, the equivalent: ambitious
missions with bunches of experiments, right at (or a little beyond) the
limits of what was reasonable then. For that matter, the original
Surveyor was also rather ambitious. (The Surveyors that actually flew
were severely trimmed down because of Atlas-Centaur performance
shortfalls, among other things, and the program was terminated before it
could work back up to the more ambitious configurations.)
Frank Crary
Henry Spencer <he...@spsystems.net> wrote:
>>>How much scientific data about the Moon or Mars have we gotten from
>>>Battlestar-class probes in the last twenty years?
>> Well, we've gotten qute a bit of data actually, as some of them fly
>>past the Moon for other destinations.
>"Some"? I count one. (Cassini made no significant lunar observations,
>last I heard.)
As I understand it, Cassini made quite a few lunar observations during
the encounter, but they were of the Earth-facing hemisphere. That
hemisphere has been studied to death (I was going to say since Galileo,
but that would be ambiguous...), so I doubt Cassini made any new discoveries.
On the other hand, those observations are very significant: As calibration
images of a very well-known object.
>...And the Galileo observations, while of some interest,
>are minor footnotes compared to what Clementine and Lunar Prospector --
>missions which *together* cost literally an order of magnitude less --
>yielded.
Sure, but those observations were basically a free bonus to the Galileo
mission. Someone (I don't feel like doing so myself) could make
an argument about the incremental costs of making those observations
compared to the value of the results. A much better case could be
made for the Ida and Gaspra observations, but you did start this
off by saying ``of the Moon or Mars.''
Frank Crary
CU Boulder
Geoffrey A. Landis
>> In the last 4 years the track record of interplanetary FBC probes has
>> been:
>>
>> Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
Deep Space 1 has to be listed as "pending" if you're calling it an
interplanetary probe and not a technology demonstration. Remember it did
*not* image asteroid Braille on the flyby. It will be interesting,
though, if it does successfully make it to the comet
>> Failure: Mars Climate Orbiter, Mars Polar Lander, Deep Space 2
>> Pending: NEAR, Stardust
In article <38518736...@NOSPAM.erols.com> rk,
stel...@NOSPAM.erols.com writes:
>...secondly, perhaps we can include clementine, which seemed to have "fbc" attributes.
Right. You will have to include it under the "Failure" column, however--
do recall that Clementine was an *asteroid* mission which stopped by the
moon on the way, and then failed before it made it to the asteroid.
--
Geoffrey A. Landis
Frank Crary
Geoffrey A. Landis <geoffre...@sff.net> wrote:
>>> In the last 4 years the track record of interplanetary FBC probes has
>>> been:
>>> Success: M.Pathfinder, M.Global Surveyor, Lunar Prospector, Deep Space 1
>Deep Space 1 has to be listed as "pending" if you're calling it an
>interplanetary probe and not a technology demonstration. Remember it did
>*not* image asteroid Braille on the flyby.
Actually, it did image the asteroid, as well as getting IR spectra. It's
``just'' that the resolution of the images was something like 50 times
worse than expected... (about 10 pixels across the disk.)
>...It will be interesting,
>though, if it does successfully make it to the comet
Actually, I think the Wilson-Harrington encounter will be more interesting:
Wilson-Harrington is the only asteroid ever observed with a tail, and
is the best known candidate for an comet/asteroid transition object.
Frank Crary
CU Boulder