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Date: Tue, 22 Dec 92 05:11:55
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #581
To: Space Digest Readers
Precedence: bulk
Space Digest Tue, 22 Dec 92 Volume 15 : Issue 581
Today's Topics:
aerospikes
Breeder Reactors
Conrad auction
DoD launcher use (2 msgs)
Earthquake Filmed from Space
fast-track failures
funding for Lunar Prospector urgently needed
Justification for the Space Program (3 msgs)
Mnemonics
MOL (and Almaz)
MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
Shuttle thermal tiles
STS-1 DISASTER/COVERUP
Terminal Velocity of DCX? (was Re: Shuttle ...)
What is DC ??
Who can launch antisats? (was Re: DoD launcher use)
Why have both manned and auto capability on DC-[XY1] & Buran?
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
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(BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: Tue, 22 Dec 1992 00:18:37 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: aerospikes
Newsgroups: sci.space
In article <ewright.724962671@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>>...driven by the one-orbit mission, whose basic rationale is deploying a
>>spy satellite -- or doing any of a number of other things -- in wartime
>>conditions where coming around again in a predictable orbit is likely
>>to result in being shot at.
>
>Of course, if the enemy has the capability to shoot at you, he also
>has the capability to shoot down that nice, new spy satellite, which
>is also in a predictable orbit...
The satellite could maneuver, or even remain captive in the payload bay
and snap its pictures during that one orbit. The USAF has not been too
forthcoming with details. :-)
--
"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
-Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: Mon, 21 Dec 92 16:33:06 -0800
From: ganderson@nebula.decnet.lockheed.com
Subject: Breeder Reactors
Session's Answer was too flipant. The reason the U.S. doesn't hav mre
ooops have more breeder reactors is that the anti-nuke forces won a battle
in the late seventies and President Jimmy Carter stopped the development
of them. The arguements given revolved around the proliferation of
Plutonium that the reactors "breed" and not on the safety of the
reactors. The nuke power industry was trying to sell them as the answer
to lmited supplies of nuclear fuel (o.k. expensive supplies) because they
produce 5 lbs of fuel for every 4 they consume. Unfortunately, the
plutonium is also a great nuke weapon resource.
It should be noted that Japan is pursuing breeders agressively. I believe
the shipment of fuel they are getting now goes toward a reactor that is
a breeder but I am not sure.
Grant Anderson
Ganderson@jedi.decnet.lockheed.com
------------------------------
Date: 22 Dec 92 02:00:30 GMT
From: Mike Smithwick <mike@rahul.net>
Subject: Conrad auction
Newsgroups: sci.space
[]
Anyone get to the auction of Pete Conrad's memorobilia that was held
a few weeks ago?
I wonder if they sold the Soviet Space suit, and if so what price it
fetched.
Also, anyone know why Conrad was getting rid of all of his stuff? Bad
gambling debts? His kids not want "daddy's junk"?? Extra pocket change
for Christmas gifts???
mike
--
This message brought to you by the Happy Fun Ball! It's Happy! It's
fun!! It's the HAPPY FUN BALL!!! (Still legal in 16 states)
*** Mike Smithwick - mike@rahul.net
*** No disclaimer is necessary since I only work for myself, HA! HA! HA! HA!
------------------------------
Date: 20 Dec 92 19:13:55 GMT
From: Gary Coffman <ke4zv!gary>
Subject: DoD launcher use
Newsgroups: sci.space
In article <1992Dec17.185953.22777@eng.umd.edu> sysmgr@king.eng.umd.edu writes:
>In article <1992Dec17.110426.8596@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes:
>>
>>The ex-Soviets have a system. Getting into a fight with them would still
>>be dealing with a serious opponent in my book.
>
>Yes, but you imply there's more than the Russians who have ASAT. Could you
>illustrate who else has demonstrated said technology? And describe the CURRENT
>state of the SS-9s (?) which were used to pitch them up?
>
>They had that capability. Whether it still exists is open to question.
I think that any nation that can put an object in a precision orbit has
the capability to knock down satellites in LEO. Only the US and the former
USSR have demonstrated that capability, but in principle it's not an extremely
difficult job, and there's really no defense against a cloud of debris in
your spysat's path.
>Besides, the Russians are our friends. We're buying reactors and science data
>and a good portion of their research establishment with good old Yankee
>Dollars.
The Russians were our friends once before this century. They were also
our opponents for forty some odd years. The winds of politics change
swiftly and easily. At least two other space powers have been our deadly
enemies at least once this century. We can't count on international politics
for our security.
>>>If you can kill recon planes, it's damn sight harder to kill sats.
>>
>>In principle no, the sats are predictable, the planes aren't. Putting
>>some "buckshot" in their orbital path is sufficient to knock them down.
>>In practice planes probably are easier to down because few countries
>>have space launch capability while they do have AAA, but most planes
>>in combat zones aren't shot down, and planes are cheaper than spysats too.
>
>Depends on what type of plane. The RF-16s are, oh, how much these days?
>$16-20 million?
Still at least 10 to 100 times as cheap as a spysat, not counting launch
costs. We usually don't do tactical recon with first line aircraft anyway.
RF-4s are still flying recon missions, though we are phasing them out as
rapidly as possible.
>>>Furthermore, you assumed that the KH-11 is the benchmark (also known as
>>>the Szabo yardstick) without the resultant drop in costs which would occur if
>>>you could rapidly deliver sats to orbit.
>>
>>Launch costs don't dominate a spysat's cost, at least not one capable of
>>doing tactical damage assessment. The cost is dominated by the superior
>>optics required for a orbital spy versus the optics required for an aircraft,
>>and by the flight control systems required to point the thing at the right
>>place and compensate for orbital motion and downlink the data. An aircraft's
>>photorecon equipment is much cheaper because the optics don't have to be as
>>good because of the lower altitude, the pilot takes care of pointing chores,
>>and the data is physically returned at the end of the mission.
>
>Gary, depending on who you listen to, the KH-12 costs between $800 mil and $1
>billion dollars, but it's also a LOT of hardware and fuel to make sure it stays
>up there for a long long time.
>
>Now, SPOT gets 5-10 meter resolution and costs some number ($150-200 million?)
>below that. A follow-on to SPOT with 1-2 meter resolution will probably cost
>the same...
>
>You CAN build a cheap sat with the resolution needed to do tactical damage
>assessment. The ex-Sovs did it all the time; they used film rather than
>rad-spec hardened long-life electronics to transmit images back. You can go
>cheap on the electronics if you don't want your spysat to live for 5-7 years.
As is usual with things related to aerospace, it's not component cost that
kills you, it's labor cost. If you started churning out thousands of spysats
on an automated assembly line, or pay your workers $40 a month, you could
get the cost down way below that of an RF-16, but that's unlikely to happen.
Precision optics with the required diffraction limits can't be churned out
by Glasses-R-Us either. Nor would film canisters be acceptable for tactical
recon today, battlefields are too fluid in modern warfare. By the time you
recovered the cansister, likely several orbits until the satellite is over a
suitable pickup zone, and developed the film, the situation on the ground
would likely have changed. Satellites are wonderful cold war tools, and good
strategic recon assets, but their use for tactical battlefield assessments is
limited by costs driven by orbital mechanics and optical resolution.
Gary
------------------------------
Date: Tue, 22 Dec 1992 00:08:17 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: DoD launcher use
Newsgroups: sci.space
In article <72109@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes:
>>we should look to develope cheap sats to go with DC-1.
>>
> I thought we were already developing cheap sats, but these are to
> go up with Pegasus, Taurus, etc.
There's cheap and there's cheap. The satellites being developed for
Pegasus etc. are *relatively* cheap because they're small... but they
still (usually) cost millions each, and they're typically built to the
same gold-plated zero-failures ten-year-life specs. Drop prices by
two orders of magnitude (not out of the question for DC-1) and many
things would have to change.
--
"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
-Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: Tue, 22 Dec 1992 00:09:27 GMT
From: "Andrew L. Alden" <alden@netcom.com>
Subject: Earthquake Filmed from Space
Newsgroups: sci.space,sci.geo.geology,ca.earthquakes
baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes:
: After precisely lining up enlarged portions of the images on
: a computer display, Crippen flickered between the two and
: observed the differing ground motions across each of the faults.
: He repeated this process with other parts of the images taken of
: several different sites along the faults, and in some cases, he
: observed newly formed cracks in the fault zones.
I watched his display both at the press conference and later downstairs,
and it was quite striking. The SPOT images are 10 m per pixel, the best
unclassified images you can get, yet even so, movements that were
measured on the ground at a meter or so were clearly visible. This is
yet another argument for declassifying space photos made by military
satellites, which are of as good quality looking down as the Hubble
Space Telescope's are looking up.
The flicker technique is used by astronomers to detect moving objects
against the backdrop of the fixed stars. The beauty of Crippen's work
is that he could get nearly the same precision using images with less
precise controls--a satellite in orbits a year apart over the same place
on the ground.
His work will pay off in similar situations where there is poor ground
control, like central Asia.
--Andrew:
------------------------------
Date: 20 Dec 92 19:25:44 GMT
From: Gary Coffman <ke4zv!gary>
Subject: fast-track failures
Newsgroups: sci.space
In article <18639@mindlink.bc.ca> Nick_Janow@mindlink.bc.ca (Nick Janow) writes:
>gary@ke4zv.uucp (Gary Coffman) writes:
>
>> When fighter development from concept to flying prototype cost less than
>> $100,000, normally funded internally by the company, and took less than a
>> year, planes were simpler then, that was an acceptable approach. Now with
>> development costs running into the billions, and usually taxpayer funded,
>> the financial risks of a failed project have become too high to take such a
>> cavalier approach.
>
>I wonder if the development of the hardware might still cost something close
>to the 1992 equivalent of $100,000...with the additional billions required
>for paperwork, politics, and legal nonsense. :-/
Today's overhead is horrible, but $100,000 1940s dollars is only about
$2 million 1992 dollarettes. I don't think you can develop a high performance
tire for that little money, much less a high performance fighter. That's
about 20 engineers in a Motel 6 for six months, no machine shops, hangers,
mechanics, flight test equipment, nada.
Gary
------------------------------
Date: 22 Dec 92 00:24:01 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: funding for Lunar Prospector urgently needed
Newsgroups: sci.space
In article <BzM3BE.GvJ.1@cs.cmu.edu> roberts@cmr.ncsl.nist.gov (John Roberts) writes:
>Realizing that it doesn't have the same instruments, is it possible that
>the recent Galileo lunar polar flyby (preliminary science press conference
>Dec 22) will tell us annything that might be helpful in making up our minds?
>Such as the exact placement of candidate craters?
It may supply some useful hints. (For one thing, if it got a good look at
the south-pole area -- I forget what exactly it was going to see well --
that would be useful for mapping, because there is a modest area near the
lunar south pole which is completely unmapped -- the Lunar Orbiters got
no usable pictures there.) It won't definitively answer the question; it
doesn't have the right instruments.
>So what happens if the government breaks what you consider to be a promise
>and decides a lunar resource mapper is a good idea? Given this "approval",
>is it possible that they would be willing to involve these guys?
Hard to call -- much depends on just how you assume the change would
happen -- but it seems possible.
There is no promise that the government won't pursue a lunar resource
mapper, but it seems unlikely at the moment. Congress wouldn't give Goldin
a measly $30M to get one started.
--
"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
-Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: Mon, 21 Dec 92 16:55:30 -0800
From: ganderson@nebula.decnet.lockheed.com
Subject: Justification for the Space Program
Denis and Dietz.
One part of your discussion disturbs me. Money can be accumulated, and
horded, and stolen. However, money must be MADE first. I'm not a
Ayn Rand (noid) but she did do a service by pointing out that the
people of the U.S. were the first to talk about MAKING money, instead
of "redistributing" it as if it was a limited resource. It is only
limited by the lack of persons willing to MAKE their own instead of
stealing others.
As to what this has to do with the justification of space, I would say that
opportunities to MAKE money are abundant in space if the technology and
resources are put to good use. This, in turn, increases the cumulative
wealth of the planet.
Grant Anderson
Ganderson@jedi.decnet.lockheed.com
------------------------------
Date: 21 Dec 1992 18:25 CST
From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space
In article <1992Dec21.163942.17983@cs.rochester.edu>, dietz@cs.rochester.edu (Paul Dietz) writes...
>I'll address Wingo's other points in another message.
>
>I asked Wingo to bring up a resource that could be obtained from
>space that was not substitutable, used in small quantities so that
>price rises could be tolerated, or in short supply. He suggested
>platinum.
>
Paul Platinum is only one of many metals that, if we have at a minimum, a
translunar transporation system would be cheaper. There is no single holy
grail that will justify the space program. Communications is one that is the
most obvious money maker today, so is weather forcasting and Global positioning
from the GPS satellites. You make the mistake, whether intentional or not, of
building a straw man to break down when you target a single technology that
may or may not be better done in space. This is not entirely your fault or
others of similar mindset, due to the unfortunate fact that the space advocacy
community also does the same thing by focusing on a single or small number
of technologies as justifications for the program. A serious considered look
at the problems of pollution, population, and wealth generation from a
systems perspective clearly show the advantage of increasing the resource
base upon which mankind must draw for survival and prosperity. I do not know
why most space advocates have not caught up with this simple fact but that
is the way it is. It seems that since the fall of Dr. Von Braun there has
been little vision for the continuance of progress in the arena of space.
We are changing this little by little. Von Braun as well as Bear Bryant is dead.
As in Alabama we have had to go for a new football coach, we in the space arena
must press forward without Von Braun. Your arguments within the narrow
context of your statements may by true. What you are forgetting is that there
is much more to this world than your perspective and your view. We must
address multiple problems that in a one on one basis are not solvable with
your solutions, or in the areas where your solutions are viable, they mean an
increase in costs, both in the areas of resource extraction and in the
area of catalyst or any other subistitution. The very process of subsitution
in engineering is one of compromising a desired quantity or quality for an
inferior one. (In most cases).
In investing the initial investment in a inner solar system space transportation
infrastructure, we open up vast resources for our use here on earth. This is
totally in keeping with five thousand years of man's experience. From the
ships of Carthage and Greece, the Roads of Rome, the Highways, Railroads,
Canals, and Airways of the modern world. This is so simple that it feels dumb
to have to relate it to an intelligent indivdual.
Wake up, look around, if we do not take this chance it may be a very long time
before the chance will come again. Do you wish to stake the future of mankind
on your suppositions? We do because we can show in myriad ways how we can
make a better tomorrow. The destiny that the dirtballers want leads in the
end to poverty and a dimming tomorrow. I cannot believe that you want that.
Dennis, University of Alabama in Huntsville
------------------------------
Date: Tue, 22 Dec 1992 02:00:21 GMT
From: Paul Dietz <dietz@cs.rochester.edu>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space
In article <21DEC199218250184@judy.uh.edu> wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov writes:
>In article <1992Dec21.163942.17983@cs.rochester.edu>, dietz@cs.rochester.edu (Paul Dietz) writes...
>>I asked Wingo to bring up a resource that could be obtained from
>>space that was not substitutable, used in small quantities so that
>>price rises could be tolerated, or in short supply. He suggested
>>platinum.
>
>Paul Platinum is only one of many metals that, if we have at a minimum, a
>translunar transporation system would be cheaper.
So, trot out your claims so I can shoot them down. And no more
of that lunar titanium nonsense, ok? I debunked that last time.
BTW, it is *not* obvious that having a translunar transportation
system would make platinum group mining economical. This system would
have costs, which could be high, as would the mining operation. Since
the market for platinum is rather small (a few billion $/year), it by
itself cannot justify much space activity.
Moreover, there's a subtle shift you're making here. I could even
agree that someday space activities could be profitable. Well,
wonderful. What I'm not willing to accept is poorly conceived
neomalthusian nonsense about space being *essential*. Apocalyptic
claims of this kind are *classic* propaganda tools, used by all
sorts of quasi-religions. They require evidence.
>of technologies as justifications for the program. A serious considered look
>at the problems of pollution, population, and wealth generation from a
>systems perspective clearly show the advantage of increasing the resource
>base upon which mankind must draw for survival and prosperity.
Blah, blah, blah. This is all vacuous mouthings. Please present
*specific* things which we can judge.
> must press forward without Von Braun. Your arguments within the narrow
> context of your statements may by true. What you are forgetting is
> that there is much more to this world than your perspective and your
> view.
I'm willing to be convinced by facts. Just what convinced you, if
not facts?
> Wake up, look around, if we do not take this chance it may be a very
> long time before the chance will come again.
Please justify that. Looks like more crap to me. The world is
getting, on average, wealthier and more productive, so I would have
thought that the future would hold more spending on luxuries like
space. Just what is it that we must do *now*?
> The destiny that the
> dirtballers want leads in the end to poverty and a dimming tomorrow.
When unable to supply a rational argument, resort to proof by assertion.
Wonderful.
Paul F. Dietz
dietz@cs.rochester.edu
------------------------------
Date: Mon, 21 Dec 92 22:46:04 GMT
From: JKF <jfurr@nyx.cs.du.edu>
Subject: Mnemonics
Newsgroups: alt.folklore.urban,sci.space
In article <1992Dec21.211902.4322@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
>system@codewks.nacjack.gen.nz (Wayne McDougall) writes:
>:
>: Oh YEAH? The planes do intersect, and there is supposed to be a collision
>: or near miss in about 4 billion years. Working backwards they should also
>: have collided about 2 billion years ago (c. 1/2 the estimated age of the
>: solar system). Some people speculate that Pluto is an asteroid that was
>: captured by Neptune at this time.
>
>Yeah - some people do make such a speculation. The same ones who ignore the
>fact that Pluto has a moon. Also, the same people ignore the fact that none
>of the asteroids travel anywhere close to that far out. They are pretty much
>confined between the orbits of Jupiter and Mars.
Sorry, Bill, but there are many planetoids and asteroids that orbit beyond
the orbit of Jupiter. One such is a minor planet called Chiron. There
are quite a few others as well.
------------------------------
Date: 22 Dec 92 00:42:47 GMT
From: Doug Davey <ddavey@iscp.bellcore.com>
Subject: MOL (and Almaz)
Newsgroups: sci.space
In article <1992Dec18.111817.24990@lmpsbbs.comm.mot.com>, dennisn@ecs.comm.mot.com (Dennis Newkirk) writes:
>
> A mockup station (really just empty Titan tankage somewhat similar in
> size to a real station) and the first test capsule (which I believe
> was the refitted Gemini 2 capsule (with the new hatch in the heatshield)
> were launched around 1970.
> Spaceflight magazine did a good history on MOL many years ago. The flight
> was interesting since during launch the second stage first put the Gemini
> capsule on a suborbital trajectory to test the heatshield during reentry,
What were the results of the "heatshield with a hatch in it" tests?
Did it work? That sure would be one door that you wouldn't want to
open at the wrong time. :-)
--
+--------------------------------------------------------------------+
Doug Davey ddavey@iscp.bellcore.com bcr!iscp!ddavey
------------------------------
Date: 22 Dec 92 00:11:40 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
Newsgroups: sci.space
In article <1h2egpINNmk9@mirror.digex.com> prb@access.digex.com (Pat) writes:
>>>You heard wrong. One MOL flew (unmanned).
>>Could somebody provide data ?
>
>According to a friend of mine who was a MOL engineer. One MOL flew
>Manned. only it was called ASTP.
He's pulling your leg. ASTP involved one Apollo, one Soyuz, and a docking
module. The docking module might perhaps have inherited a bit of technology
from MOL, but no way was it a MOL. For one thing, it was a fraction of the
size.
--
"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
-Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 21 Dec 1992 23:27:54 GMT
From: "Kevin W. Plaxco" <kwp@wag.caltech.edu>
Subject: Shuttle thermal tiles
Newsgroups: sci.space
In article <1992Dec21.171239.25448@eng.umd.edu> sysmgr@king.eng.umd.edu writes:
>
>A call to the Russian embassy or Glav-whomever, perhaps? Say you're a
>researcher and offer 'em $20 bucks (U.S.) for the data. Heck, $30 and shipping
>would probably get you a used Buran tile. :)
A friend who works with Payload Systems (the folks who pissed off the
pro fred crowd with the "micro gee xtalography is not really any
better than 1 gee xtalography" paper in Nature recently) was *GIVEN*
a free Buran tile last time he visited space city (or whatever it is
they've decided to call the place). It's surprisingly dense.
It's got a tacky plastic copy of a Proton glued to it.
-Kevin
------------------------------
Date: 21 Dec 92 20:33:30 GMT
From: Thomas Hagadorn <hagadorn@amsaa-cleo.brl.mil>
Subject: STS-1 DISASTER/COVERUP
Newsgroups: sci.space
In article <1992Dec21.110606.2970@cnsvax.uwec.edu> mcelwre@cnsvax.uwec.edu writes:
>
>
>STS-1 DISASTER/COVERUP
>
>Dr. Beter AUDIO LETTER #64 of 80
<...much sophomoric conspiracy theory deleted...>
I guess it's time to go back to the kill file for Bob. There is a
newsgroup for this stuff already (alt.conspiracy) without adding
to the noise in this group. Then again, maybe it should go to rec.humor
as a send-up of the Illuminati series (but, it needs some work)...
------------------------------
Date: 20 Dec 92 19:55:20 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space
In article <1gt36dINNq3h@mirror.digex.com> prb@access.digex.com (Pat) writes:
>
>I believe in point of fact, that is the whole point of the DC-Y.
>DC-X will prove the operations and technology. DC-Y will push the
>envelope to LEO, and test the new engines. DC-1 is then production.
>
>Given the low cost of the DC-X,Y test program, we should be advocating
>the completion of the test program. If it succeeds, then we should
>all feel good. if it costs too much, we should head back to the
>drawing boards. God knows, maybe HTHL is the way to go for cheap
>space flight and gary gets to say "I told you so" 1x10(6) times.
I hope the DC program all works and we get cheap and frequent access
to LEO, but I don't think it'll operate at airliner costs or schedules,
or that it will be allowed to land at metropolitian airports as some
have already accepted as fait accompli. Besides, if it doesn't work,
I'll only tell you I told you so 10^3 times. :-)
>My gut feel, is that SSTO will always be cheaper then Stacked rockets.
>Now if there is some way to get useful payload to orbit in an SSTO,
>we will see.
It depends on how much useful payload we need to lift at a shot and
how cheap on orbit assembly gets. We haven't exhausted the things we
can do with small payloads, but there are also things we'd like to
do that require larger payloads. I contend that on orbit assembly
won't get cheap enough soon enough to let DC carry nuts and bolts
to orbit. It'll still be more cost effective to assemble and test
the bulk of space payloads on the ground and boost them to orbit
on larger capacity launchers, especially if some effort is put into
designing a heavy lifter for low labor costs.
Gary
------------------------------
Date: Tue, 22 Dec 1992 00:16:04 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: What is DC ??
Newsgroups: sci.space
In article <HUGH.92Dec21190917@whio.cosc.canterbury.ac.nz> hugh@whio.cosc.canterbury.ac.nz (Hugh Emberson) writes:
>Henry> Note that Atlas did it with a stage and a half -- dropping two
>Henry> engines but nothing else -- in 1958...
>
>How did Atlas drop its engines?
At the rear of an Atlas there are three engines, in a row. The outer two
are mounted on/in a short structural ring that forms the lowermost part of
the outer surface of the Atlas. At staging, the ring falls off, taking
the two engines with it. The center engine continues to burn. Fuel feeds,
electrical connections, etc., are disconnected as the ring separates.
I believe the outer engines shut down just before separation.
--
"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
-Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 21 Dec 92 22:41:14 GMT
From: Bill Higgins-- Beam Jockey <higgins@fnala.fnal.gov>
Subject: Who can launch antisats? (was Re: DoD launcher use)
Newsgroups: sci.space
In article <1992Dec20.191355.2914@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes:
>
> I think that any nation that can put an object in a precision orbit has
> the capability to knock down satellites in LEO.
Reasonable.
> Only the US and the former
> USSR have demonstrated that capability, but in principle it's not an extremely
> difficult job, and there's really no defense against a cloud of debris in
> your spysat's path.
Only the US and the former USSR? I think ESA, ISAS, NASDA, and Great
Wall, Inc. might disagree with you. They might also point out that
Israel and India have launched satellites on multiple occasions, and
ask you how you define "precision orbit." France, Britain, and Italy
are kind of retired from the launch business, but they are ESA
partners. Brazil is coming up fast as a contender here.
Bill Higgins, Beam Jockey | "Enough marshmallows
Fermi National Accelerator Laboratory | will kill you
Bitnet: HIGGINS@FNAL.BITNET | if properly placed."
Internet: HIGGINS@FNAL.FNAL.GOV | --John Alexander, leader of
SPAN/Hepnet: 43011::HIGGINS | "disabling technologies"
[*Aviation Week*, 7 Dec 1992, p. 50] | research, Los Alamos
------------------------------
Date: 20 Dec 92 19:37:23 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Why have both manned and auto capability on DC-[XY1] & Buran?
Newsgroups: sci.space
In article <1992Dec18.011309.12639@bby.com.au> gnb@baby.bby.com.au (Gregory N. Bond) writes:
>I understand the DC-X will, like the xUUSR Buran shuttle, have
>capabilities for both unmanned automatic operation and piloted
>operation. I suspect similar capability is expected for DC-Y and DC-1
>should they be built.
>
>Given that the thing can fly automatically, why add pilots?
>
>I'm not sure what manned piloting means in this context, and what it
>gains over auto operation; especially since providing space, controls,
>seats, life support etc for the pilots is very expensive on the mass
>budget.
>
>In what sense is the Shuttle piloted? What about Apollo?
>
>[I'm not talking here about the capacity to _carry_ people, and I
>certainly don't want to start the manned-vs-unmanned flamewars again;
>I'm strictly refering to the actual driving of the craft.]
Theoretically, Shuttle has had autoland from the beginning, but it's
never been used. Similarly, in space rendezvous and docking is handled
manually. Normal ascent, descent, and station keeping are handled
automatically. With Apollo, the state of the art in automatic flight
controls of the time would have put Eagle in a boulder field rather than
Tranquility base. The docking between the LEM and the command module was
also a manual eyeball operation. Fully automatic operation for routine
flights should be fairly easy today. Like with modern airliners, the pilot
is just along as an exception handler. The ex-Soviets have been doing
routine Progress flights for some time.
Gary
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End of Space Digest Volume 15 : Issue 581
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