I'nnit true that there is LOX and LH2 to spare in ET on lower-altitude
launches? I.e., for this mission they burned longer on the ET fuel,
instead of discarding the ET only partially emptied?
_______________________________________________________________________________
| | | | |\ | | /|\ | John K{llen The above is a figment of your
| |\ \|/ \| * |/ | |/| | | PoBox 11215 overworked imagination. Take 2
| |\ /|\ |\ * |\ | | | | Stanford CA 94309 aspirin and call a doctor.
_|_|___|___|____|_\|___|__|__|_j...@neon.stanford.edu___________________________
My question is this, though -- since the telescope is the heaviest
payload ever launched, and the orbit is the highest ever acheived
in the shuttle, why was there no need for the OMS burn after MECO?
"... the Univerise is still 'go' ... "
--
Michael V. Pelletier | "We live our lives with our hands on the
CAEN UseNet News Administrator | rear-view mirror, striving to get a better
Systems Group Programmer | view of the road behind us. Imagine what's
| possible if we look ahead and steer..."
The SSME's are capable of putting the Shuttle into orbit directly;
this has been done a few times in the past in addition to this launch.
Usually, the equivalent of an OMS 2 burn is needed to circularize the orbit.
The way I understand it, the normal system of 2 burns is used so that the
ET does not go into orbit with the Shuttle; having something that large in an
orbit close to the Shuttle might be hazardous to the astronauts' health.
--
jabi...@uokmax.ecn.uoknor.edu
"I'm President of the United States and I'm NOT going to eat any more
broccoli!" -- George Bush
Don't forget that the higher you go the more OMS fuel required to de-orbit.
I'm sure the altitude constraint is based on having enough ET fuel to cover
normal vehicle performance variations _and_ to be able to de-orbit with the
Hubble still aboard in case problems are discovered during its deployment,
again including normal performance variations and reserves.
----------------------------------------------------------------------
Dave Dodson dod...@convex.COM
Convex Computer Corporation Richardson, Texas (214) 497-4234
The HST may have gone up the highest, but that should require the orbit
to have the most energy. Isn't it supposed to be a highly eliptical orbit?
Stephen Uitti
sui...@ima.ima.isc.com
This still doesn't answer the question of why they didn't use the OMS
engines during the HST launch. If they want the highest shuttle orbit, you
would think that they would fire the OMS engines a couple of times in
addition to whatever else they did to get the shuttle into a higher than
normal orbit.
John L. McKernan. jm...@sun.com
Disclaimer: These are my opinions but, shockingly enough, not necessarily Sun's
-------------------------------------------------------------------------------
There is a *little* bit of fuel to spare on lower-altitude launches, some
of which gets used on things like secondary payloads and higher-inclination
orbits. Not a lot.
--
If OSI is the answer, what on | Henry Spencer at U of Toronto Zoology
Earth could be the question?? | uunet!attcan!utzoo!henry he...@zoo.toronto.edu
They did use the OMS engines. They used an OMS-2 burn to circularize.
Otherwise, they used the SSME's longer to get to the higher altitude.
Peter Jarvis...
Craig Alexander **** cale...@castor.usc.edu
BUT --
Do all orbiting devices travel in the same direction? Do they all orbit in
the direction of the earth's rotation? Geosynchronous satellites, of course,
have a good reason for going that way. Is there any reason that a satellite
might go the other way to pass over the earth's surface as many times as
possible? If so, some of this space junk could collide with still-useful
satellites at an incredible speed!
LOOK OUT!!!
Kerry
P.S. I just figured out the flaw in my reasoning. What about polar orbits,
and anything else in between them and equatorial orbits. Yow!
-----------------------------------------------------------
Gary A. Therens g...@hare.udev.cdc.com
Control Data Corporation (612) 482-4272
No; low Earth orbit at minimum inclination for KSC launch (28.5 degrees I
think), to maximize orbital altitude for a large and heavy payload.
Sun-synchronous polar orbit with the aperture always pointing outward,
away from both Earth and Sun, is ideal for sky-survey missions like IRAS
and COBE, but is of limited use to things like HST that want to point in
random directions. It's more expensive to launch into than a low-inclination
orbit, which means either lower payload or lower altitude.
--
If OSI is the answer, what is | Henry Spencer at U of Toronto Zoology
the question?? -Rolf Nordhagen| uunet!attcan!utzoo!henry he...@zoo.toronto.edu
In the past, the usual approach was to ignore the issue. Of late, it's
become clear that it can no longer be ignored. NORAD tracks all the big
stuff, and shuttle missions and the like are checked against NORAD's
tracking file, but there is a lot of little debris that is an increasingly
worrisome problem. Nobody is really sure how much of it is up there, in
fact, but there have been disturbing incidents like the little crater in
the shuttle window, and examination of things like LDEF and the parts
brought back down after the Solar Max repair shows a lot more debris
cratering than expected. The odds of serious damage to HST are small,
but they are not zero, and there is reason for concern.
>Sort of on the same subject, if/when our waste problem on earth becomes
>too much to handle here, and if it were feasible cost-wise, would there
>be any problem with sending it into space, headed directly for the sun?
The cost looks to be much higher than that of dealing with the stuff here,
with the possible exception of the very nastiest items like long-lived
radioactive waste. Launch failures are also a worry. Those issues aside,
it's not inconceivable.
--
I don't know that much about space 'junk' but I am getting a tour and interview
at a navy site outside of town whose only function is tracking 'stuff' in orbit.
In a brief telephone conversation with the site, I was told thre are 'thousands'
of things in their orbital catalog. Why the navy? Got me.
The interview is for an article I'm writing. I could upload the text if there
is sufficient interest.
John
The North American Aerospace Defense Command at Colorado Springs tracks
most of it above a certain size. They don't say what size, but I've
heard that they can track a metal object 2 inches in diameter. Supposedly
they keep tabs on over 10,000 objects.
That's a lot of nuts and bolts.
--M. G.
It's not really feasible because of the cost per pound to put it on a
trajectory to the sun is too high (with current technology). I believe
Jerry Pournelle said that the cost per pound to orbit something would
be about the same as to fly it from Los Angeles to Sydney if the
government would get out of the way, but that's still too high.
As for radioactive waste, the problem is simpler than most believe, but
companies like Westinghouse and bureaucracies like the Energy department
and certain environazis have a vested interest in making it look hard.
The volume of radioactive waste, both low and high-level, is not great,
and besides, in a few years we may have some worthy uses for the
radioactive fractions. Can't make any more uranium, and it would be a
shame to just throw it away.
After all, a few years ago no one knew what to do with old tires. Now
they are being reused in several different, environmentally sound ways.
--M. G.
I think that trying for a perment way to get rid of nuclear waste may
well end up annoying the heck out of our grandchildren who may wish
we had just stuck it away where they could get at it and use it. It
sounds corny but todays waste may well be tomorrows treasure!
Scott
Buttered bread always lands * Scott McGee
butter side down! (Unless * email : smcgee%alb...@cs.utah.edu
it sticks to the ceiling!) *
Would YOU mistake these opinions as anyone's but my own?
Sort of on the same subject, if/when our waste problem on earth becomes
too much to handle here, and if it were feasible cost-wise, would there
be any problem with sending it into space, headed directly for the sun?
I've always thought this is a brilliant idea, but I don't know what
sort of consequences would follow at all, so if anyone knows...
Also, any problems sending radioactive waste in the same direction?
Sorry if my stupidity in this is overwhelming.=>
thanks in advance!
-Paul V. Brown
pb10...@tutor.tut.fi
The problem with this is that it won't ever be cost effective. For the
forseeable future, the cost of space flight will remain prohibitively
expensive. Please bear in mind that the "official" cost of putting one pound
into Low Earth Orbit is about $3000 aboard the Space Shuttle. That doesn't
even get it out of Earth orbit and into a heliocentric orbit...
--
Tom Egelston Internet: t...@uokmax.ecn.uoknor.edu
Disclaimer: Don't get so stressed!! It's nothing but a bunch of 1's and 0's...
"Though my eyes could see, I still was a blind man,
Though my mind could think, I still was a mad man..." -- Kansas
Even if we could catalog the big stuff, the little stuff could still
cause havoc. Several years ago, Challenger came back from a mission with a
rather large gouge on one of its windows; it was later determined that the
gouge was caused by a tiny paint chip. Also, if I'm not mistaken, one of the
Salyuts was hit by some micro-object which actually pierced its hull; the
cosmonauts were able to fix it easily.
Junk in low orbit eventually comes down. A bigger problems is the zone
for geosynchronous orbits; stuff stays up there a lot longer, and the band is
pretty narrow to begin with.
This is one reason why crashing the stuff into a particular lunar crater
is a better space-disposal method than dropping it into the Sun. (It's
also cheaper.) That makes it recoverable, at least in principle. Costs
still make it more attractive to deal with the stuff on Earth, though --
the obstacles to doing so are political, not technical.
--
Hmm... is even this necessarily true? If both objects are in elliptical
orbits, for example, they might meet when one is at its perigee and moving
fast, while the other is at apogee and just loafing along. Their speeds
would be different as well as their directions.
Or is my orbital mechanics flaky?
(This isn't to say that I think most or many objects are in such orbits,
I'm just proposing a mechanism for differing speeds at the same altitude.)
True; I oversimplified a bit. Circular or near-circular orbits are rather
more common than seriously elliptical ones, barring one or two special
cases like GTO.
I think everyone has been missing the point about this.
I don't think that we should be shooting off our problems into space, we
created it, we have to deal with it. Also, does anyone know for sure
what happens when you send radio active waste into the sun? Sure the
containers (spacecraft and barrels) it is in will burn up before it
actually hits the sun, but energy is not destroyed. What happens to the
molecules (radioactive possibly) that are left after the burn up? Do
they get swept up by the solar winds and rain down on the earth in 100
years?
Earth day ment clean up the earth, not dirty up space.
Speed != velocity. Everything at the same altitude is moving at roughly
the same speed, but the directions are different. Even assuming a single
(Northern hemisphere) launch site launching at minimum inclination, a noon
launch will put the northernmost point of the orbit on the sunward side of
Earth, and a midnight launch will put said point on the spaceward side, with
those two orbits intersecting at the day/night boundaries. And of course,
in real life there are half a dozen major launch sites using a variety of
inclinations, and various precession effects that gradually alter orbits.
>Do all orbiting devices travel in the same direction? Do they all orbit in
>the direction of the earth's rotation? ...
Most of them, more or less. Launching eastward adds the Earth's rotation
to the rocket's speed, which increases payload to orbit. This is useful
enough that launches in other directions occur only when there is a specific
reason. (The usual reason is desire for a polar or near-polar orbit, for
one of several reasons.) However, the different latitudes of the various
launch sites give different orbital inclinations for due-east launches.
>... Is there any reason that a satellite
>might go the other way to pass over the earth's surface as many times as
>possible? ...
Not usually. Retrograde orbits are not very useful. Apart from a small
scattering of experimental launches in the early days, the only folks who
launch into retrograde orbits are the Israelis. They do it because
they don't have a lot of choice if they don't want the launch trajectory
to pass over hostile neighbors.
(NB to the pedantic: I am using "retrograde" here to mean seriously
retrograde, not polar orbits that are technically retrograde by virtue
of inclinations slightly exceeding 90 degrees.)
--
Nick
P.S. Were the FOBS tests retrograde (I know they were < 1 orbit ) ?
--
Dr. Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: ni...@syma.sussex.ac.uk BITNET: nickw%syma.sus...@uk.ac
Eventually, most of them get spewed out into interstellar space, along
with the vast tonnage of radioactive trash the Sun constantly spews
out naturally. The most concerted human efforts, with our near-future
capabilities, could not possibly make a measurable difference in the
level of space pollution.
>Earth day ment clean up the earth, not dirty up space.
Earth Day unfortunately didn't seem to mean quantitative thinking to any
great extent. Before decrying something as horrid and unacceptable, one
should figure out just how much difference it makes.
--
Our company is currently working with NASA and one of its contractors
concerning emergency medical equipment. Cost per pound to orbit on
a Shuttle is around $66,000.
Peter Jarvis....
Think about this for a while. You've damaged the environment and spent $X
to mine, refine, synthesize and otherwise produce some useful material:
metal, glass, plastic, whatever. You now want to take this useful material
and place it completely out of reach, *forever*, so you will then have to
go back and create *more* environmental damage and spend more $$ to mine,
refine, synthesize and otherwise produce more of the same stuff you had
in your hands a momemt ago. Brilliant idea???
What needs to be blasted into the sun is this throw-it-away mentality.
Try this: Next time you throw something away, think about how much sense
it would make to just toss it into your backyard - or if you're an
apartment dweller, under your bed. Make sense? No. Then why is it any better
to toss it on a pile a few miles away?
We need to create facilities to RECYCLE materials: metal, glass, plastic,
chemicals, nuclear "waste". "Out of sight, out of mind" is not the answer.
--
--Larry: 74017...@compuserve.com
It's been a few years since I was there, but I seem to recall that the
last time I toured NORAD they mentioned that they were still tracking
the electric screwdriver that floated away during the Solar MAX
mission...
In insignificant amounts, yes.
: Earth day ment clean up the earth, not dirty up space.
Your notion of how "clean" interplanetary space is happens to be about 30
years out of date. The solar wind is pretty "hot", radioactively speaking.
Larry Wall
lw...@jpl-devvax.jpl.nasa.gov
I believe the biggest problem with sending waste up is the possibility
of launch failure. I mean transporting the stuff on state highways is
difficult enough because you have to protect against an accident at 55
mph, much less... As for keeping the stuff here because you might
want it again, there's not a whole heck of a lot you can do with scrap
steel piping with low-level contamination from a power plant. It's
got no power worth recovering, and there will always be cheaper ways
of obtaining iron than molecule by molecule disassociation. (I'd
wager that cost more than recovering it from extra-terrestrial
sources.)
Joe Wagner jo...@ncar.ucar.edu
Nuclear Waste -- can't live with it, and if we don't get off our
duffs in a few years, can't live without it.
>In insignificant amounts, yes.
>
Well actually, the radioactive debris would be back at earth distance in about
8 minutes to 8 days. The amount would be TINY or less because it would be
spread out over a terribly wide area. Besides, IF every ATOM of atomic
material that is currently on/in/ or associated with planet earth WERE dumped
into the sun, the TOTAL output in relation to the constant output of the sun
would be less than the average output from solar flares for a day. In other
words, I doubt if it could even be measured with todays instruments. This
isn;t to say that we shouldn't clean up the earth.
al
>In insignificant amounts, yes.
>
#...Besides, IF every ATOM of atomic
#material that is currently on/in/ or associated with planet earth WERE dumped
#into the sun, the TOTAL output in relation to the constant output of the sun
#would be less than the average output from solar flares for a day. In other
#words, I doubt if it could even be measured with todays instruments.
#This isn;t to say that we shouldn't clean up the earth.
#al
A crucial difference is of course that the sun pumps out radiation
i.e. accelerated particles, but does not produce radioactive particles
which can sit around waiting to accumulate inside a body where they
can get nice and close to those crucial blue-print thingys before
"going off." As I understand it, the problem with waste isn't the net
amount of radiation which is produced, but that the radioactive
particles can accumulate inside biological systems, where what decays
is sure to hit something important.
Speaking of Radiation, does anyone know how quickly the shuttle can
be recalled if there is a solar event? Also what would be the longest
delay if the shuttle was into a more exposed polar orbit?
Joe Wagner jo...@ncar.ucar.edu
This may well be true NOW but who can say what the case may be in 50 years.
I still say, take all this radioactive waste and put it in a nice safe hole.
I would be willing to bet that in just a few decades someone will be wanting
to get it back because it has become economically (or, possibly, just
enviromentally) viable to process and reuse it.
Like I said previously, petroleum (and natural gas too) were once very anoying
things to be gotten rid of. The are now (needless to say) in very high demand.
Now, why would anybody think that?! All the radioactive elements that
exist were either created inside a star or result from the breakdown
(natural or artificially induced) of some that were. The sun and the
other stars in the universe are the prime (and virtually only) source
of ALL the larger elements. Helium is the only one that MAY be produced
in large quantity outside of stars. (I don't know how much is but I
will concede that it may. The rest ... no way!)
In fact, the problem is REALLY serious now. It has been reported that on one
window of the shuttle, the density of micrometeoritic impacts is the same
after 5 days of mission as the one for skylab after one year (based on the
data gathered by the last Apollo crew to go there in 1973...). The problem
is such that NASA has given spacial guidelines for EVA and during
the decompression of SASs to prevent the spread of further garbage in
low orbit. Experts agree that if nothing is done, within 10 years going into
orbit will become a risky entreprise, for there will be billions if not
trillions of sub-millimetric particles scattered in at all altitudes and all
inclinations. Some of them will of course come back, but it takes centuries
for even a small particle to go down from 600 km. The problem is that there
will be an accumulation zone over 1000 km which will create a form of "rain"
of debris going into lower orbits. The real trouble here is that the increase
is quasi-exponential: Particle collide between themselve, creating new
material, old russian cosmos's crowd the 1000 km orbits, providing an endless
reservoir of garbage, past and present military experiments are still
involved in explosion tests... I guess the future is very pessimistic,
and I'll be happyn if hubble lives up to its first anniversary in orbit.
| Mark S.
If you think americium leaking into the ground water is unpleasant,
just imagine it vaporized and spread out over the countryside....
As for ordinary waste, in the long term there is a possible problem
with depleting the earth of raw materials; in the short term, I believe
a single large city produces considerably more garbage in a year than
the total tonnage we've put into space in thirty years.
The basic contradiction is -- the only waste that's so dangerous we
can't tolerate it here on Earth is stuff we can tolerate even less
being sprayed into the atmosphere by a "major malfunction".
--
Tim Maroney, Mac Software Consultant, sun!hoptoad!tim, t...@toad.com
"Next prefers its X and T capitalized. We'd prefer our name in lights in
Vegas." -- Louis Trager, San Francisco Examiner
No, the FOBS tests were at 49.7 degrees inclination.
Highly retrograde satellite list: (i > 115)
(I believe this list is essentially complete.)
Launch Name peri/km x apo/km x inc/deg
1964 Jun 13 CORONA KH-4A/Starflash reentered 1965 from i=115.0
1964 Jun 13 Starflash 1A part reentered 1964 from i=115.0
1964 Jun 13 CORONA SRV recovered 1964 from i=115.0
1964 Aug 21 CORONA KH-4A/Starflash reentered 1965 from i=115.0
1964 Aug 21 CORONA SRV recovered 1964 from i=115.0
1965 Aug 28 OV1-2 409x2895x144.2
1965 Aug 28 Altair X-258 rocket 410x2794x144.2
1966 Mar 30 OV1-4 885x1010x144.5
1966 Mar 30 Altair X-258 rocket 886x1008x144.5
1966 Mar 30 OV1-5 985x1058x144.6
1966 Mar 30 Altair X-258 rocket 987x1057x144.6
1966 Mar 30 OV1-5 sensor cover 854x 963x144.6
1966 Mar 30 OV1-5 sensor cover 859x 961x144.6
1966 Apr 19 GAMBIT KH-7/Agena D reentered 1966 from i=117.0
1966 Apr 19 GAMBIT SRV recovered 1966 from i=117.0
1966 Jul 14 OV1-8P reentered 1978 from i=144.3
1966 Jul 14 Altair X-258 rocket 946x 973x144.2
1966 Jul 14 OV1-8P container half 999x1012x144.2
1966 Jul 14 OV1-8P container half 974x 987x144.2
1966 Jul 14 OV1-8P part 999x1008x144.2
1968 Jul 4 Explorer 38 5829x5867x120.8
1968 Jul 4 TE-M-479 rocket 5824x5863x120.9
1968 Jul 4 TE-M-364 rocket 668x5756x120.7
1968 Jul 4 TE-M-364 part 619x5774x120.7
1974 Jul 14 NTS 1 13446x13773x125.0
1974 Jul 14 PTS rocket reentered 1980 from i=125.0
1974 Jul 14 NTS 1 apogee motor 13446x13773x125.0?
1975 Apr 9 GEOS 3 819x851x115.0
1975 Apr 9 Delta 2910 rocket 789x854x115.0
1975 Apr 9 GEOS 3 part 777x885x115.2
1975 Apr 9 GEOS 3 part 844x1012x115.0
1975 Apr 9 GEOS 3 part reentered 1983 from i=115.0
1988 Sep 19 'Ofeq 1 reentered 1989 from i=142.9
1988 Sep 19 Shaviyt rocket reentered 1989 from i=142.9
1990 Apr 3 'Ofeq 2 206x1586x143.2
1990 Apr 3 Shaviyt rocket 206x1586x143.2
#Now, why would anybody think that?! All the radioactive elements that
#exist were either created inside a star or result from the breakdown
#(natural or artificially induced) of some that were. The sun and the
#other stars in the universe are the prime (and virtually only) source
#of ALL the larger elements. Helium is the only one that MAY be produced
#in large quantity outside of stars. (I don't know how much is but I
#will concede that it may. The rest ... no way!)
#Scott
Come now, don't forget that heavy particles are only produced in any
quantity when a star's getting that old kinda feeling. We'd be
seriously bumming if the sun was producing any heavy elements right
now. I can't recall off hand, though I suppose I could look it up,
but I don't think the sun has the mass to make radioactive particles
even if when it does die out.
Joe Wagner jo...@ncar.ucar.edu
"Obviously I can't speak for the real experts who work here, but heh,
what's bandwidth for..."
Does any one have an up-todate, (as of 14/5/90) long range (3
years +) shuttle flight manifest including orbiter /payload
information.
Many thanks M.sean Bennett & Marc Richardson