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Date: Mon, 24 May 93 05:00:09
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #617
To: Space Digest Readers
Precedence: bulk
Space Digest Mon, 24 May 93 Volume 16 : Issue 617
Today's Topics:
Boeing TSTO concept (sort-of long) (4 msgs)
Camera falling from space for Home Movies!?
DC-X info?
Earth to Mars Shuttle and cost!?
Galileo Update - 05/21/93
Hey Sherz! (For real!) Cost of LEO
Moon Base
Murdering ET (was Re: murder in space) (3 msgs)
murder in space
SDIO kaput!
SDI RIP. So what happens to DC?
Space Marketing would be wonderfull.
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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(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: 23 May 1993 12:18:54 GMT
From: John F Carr <jfc@athena.mit.edu>
Subject: Boeing TSTO concept (sort-of long)
Newsgroups: sci.space
In article <schumach.738098252@convex.convex.com>
schumach@convex.com (Richard A. Schumacher) writes:
>These would be No Fun on surfaces intended to create lift. Yes, I
>know there are tiles on the Shuttle wings; the Shuttle lifts like
>a brick. (Trivia question: how fast would a Shuttle have to move
>to actually gain altitude using only its wings?)
The wings generate lift equal to shuttle weight in normal flight, more than
that during the final turns and flare to landing. This is at speeds under
300 knots. 1g + epsilon is what it takes to climb. It isn't lack of lift
that keeps the shuttle from climbing; it's excessive drag and insufficient
thrust. A shuttle probably could be made to climb. Once. Briefly. After
that the pilot gets to practice stall/spin recovery. (Has NASA developed
spin recovery procedures for the shuttle? or does the book just say "don't
do that"?)
--
John Carr (jfc@athena.mit.edu)
------------------------------
Date: 23 May 1993 11:48:14 -0400
From: Pat <prb@access.digex.net>
Subject: Boeing TSTO concept (sort-of long)
Newsgroups: sci.space
In article <C7E7DJ.9uu@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>I'm told that Boeing eventually decided to dispense with the SSME in the
>tail, having discovered a better trick: inject liquid hydrogen (I think
>it was) into the bypass ducts of the regular 747 engines, and burn it
>there. The increase in thrust is tremendous, and apparently it doesn't
>hurt the engines much if you only do it for 30 seconds per flight.
I guess that makes Nitrous injection look pale :-) How would this
differ from a conventional afterburner? And what a comment on
robust engine design where you can do something this dramatically
different and not collect on your life insurance.
If they seriously boost thrust, did they have to rre-design
the thrust pylons?
Also what a trick for short field take off. really wow the crowds
asa 747 fully loaded takes off, straight up :-)
pat
------------------------------
Date: 23 May 1993 11:52:51 -0400
From: Pat <prb@access.digex.net>
Subject: Boeing TSTO concept (sort-of long)
Newsgroups: sci.space
In article <C7G7st.DEG@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
|The B-58 wasn't capable of Mach 3 even in a dash, and neither the SR-71
|nor the X-15 was made of aluminum. (The SR-71 was mostly titanium, and
|the X-15 used titanium for its *low-temperature* structure plus various
>refractory metals for the hot stuff.)
How about the XB-70?
pat
------------------------------
Date: Sun, 23 May 1993 14:47:41 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Boeing TSTO concept (sort-of long)
Newsgroups: sci.space
In article <C7G7st.DEG@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>
>The crucial question is, are we talking about an operational transportation
>system, or a low-duty-cycle research aircraft? Marginal approaches won't
>cut it for operational transportation -- there you need safety margins
>and fault tolerance.
I have this rifle, it was built just before the turn of the century.
It was designed to withstand 50,000 PSI of 4,000 degree gases for
2 to 3 milliseconds at a time. It will fail if exposed to as little
as half a second of the same conditions. Does that make it marginal?
Of course not, it's perfectly adequate for it's designed job, and
has been for nearly a hundred years of service. The same thing applies
here. The SST boost phase is of limited duration because of engine
and fuel constraints. You'll run out of liquid hydrogen to dump in
the engines long before the heat limits of the structure are reached.
We are talking about taking a mach 2 SST and giving it a very short
mach 3 dash capability after all. It's not expected to *sustain*
such speeds. Even the simple aluminum honeycomb structures used on
B-58 and B-70 should be adequate to the task. If you want overkill,
substitute titanium for aluminum in the leading edges.
>>... Active cooling for the necessary
>>short dashes might be easiest, but even Shuttle tiles or thermal blankets
>>might do for passive protection...
>
>Except that adding *external* insulation means throwing most of the old
>aerodynamic test results in the garbage -- you're dealing with something
>approaching a new aircraft. You don't just casually slap insulation on
>the leading edge of a wing; the slightest change in leading-edge shape
>makes a big difference to the aerodynamics. And a fatter leading edge,
>in particular, is seriously bad news for supersonic drag.
Then don't make the leading edge fatter. Keep the same airfoil, just
recess the supports to handle the thicker tiles. (Not that I think
tiles are the best answer, too porous, but it's feasible if you stay
out of rainstorms.) After all, the *detail* design of the internal wing
ribs for this SST *concept* vehicle hasn't been done.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Sun, 23 May 1993 15:21:05 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Camera falling from space for Home Movies!?
Newsgroups: sci.space
In article <1993May22.232938.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes:
>Wierd idea time:
>
>How hard would it be to design, build and get on the shuttle a television
>camera package that would be ejected into orbit to enter the atmosphere in such
>a way to get pictures on its way down?? Namely for an episode of 'home movies'
>or other like shows.. I bet it owuld be a cool thing to watch the TV camera
>package falling to burn up (in a safe place)...
That's an interesting question, and relevant to some of the original
SDI type scenarios. Terminal targeting through the plasma sheath formed
during re-entry was a major concern of the "smart crowbar" strawman
proposal. I haven't seen the details released, but apparently there are
ways to do it.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: 23 May 93 11:18:43 GMT
From: "Kim B. Larsen" <kiml@aho.no>
Subject: DC-X info?
Newsgroups: sci.space
Could anybody direct me toward some comprehensive info on the DC-X?!
Kim Baumann Larsen, civil architect
Oslo School of Architecture, Oslo, Norway email:kiml@aho.no
------------------------------
Date: Sun, 23 May 1993 15:14:46 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Earth to Mars Shuttle and cost!?
Newsgroups: sci.space
In article <1993May22.225921.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes:
>Wierd question time again!
>
>What would be cheaper, having a 'shuttle' or a 'lander' or a 'DC-X' to land on
>Mars? Im not talking a one time event, I'm talking taking off from Earth, then
>fly to Mars and land.. a real 'shuttle' basically a Earth to Mars Shuttle.
>
>Or would it be better to have a shuttle to orbit, 'mars shuttle' and then a
>lander on Mars.. (A three step even)..
If the run is going to be regular, frequent, and continuing, I don't
think there's much doubt that the latter 3 step option (with a station
at each end to smooth scheduling and logistics) would be the best. Each
piece can be optimized for it's very different mission profile. If there
are to be only a few, or one, Mars missions, a Mars direct approach would
be cheaper. Think of it like a railroad with piggyback terminals at each
end rather than a fleet of over the road trucks. The former is more efficient
if there is sufficient volume heading in the same direction.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: 23 May 1993 11:32:35 -0400
From: Pat <prb@access.digex.net>
Subject: Galileo Update - 05/21/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary
about The HGA.
I know it was left furled until post venus, because of
therma concerns. but what exactly? the mesh, the focal
elements?, the rods??????
I may have asked this before, but my short term memory
doesn't work so well these days.
thanks
pat
------------------------------
Date: 23 May 1993 17:13:45 GMT
From: Pawel Moskalik <pam@wombat.phys.ufl.edu>
Subject: Hey Sherz! (For real!) Cost of LEO
Newsgroups: sci.space
In article <C7Gv89.K1z@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>
>And a claim of "most mass to LEO" for *any* Western launcher is silly,
>when the USSR/Russia has launched 1200+ "A" boosters, each with a payload
>of several tons to orbit.
According to Launch Vehicle Directory (Flight International Apr 13)
Soyuz launcher hasbeen launched succesfully 994 times.
Molniya launcher (four stage version of Soyuz) has been launched
succesfully 250 times.
There have been also many succesfull launches of Vostok launcher
(88 between 1970 and 1988 any many before that, I do not have
complete numbers). All these rockets belong to "A" family of boosters.
Let's limit our calculation to Soyuz (Molniya is not flying to LEO and
for Vostok I do not have the number in hand). Soyuz delivers
7500 kilograms to LEO.
7500 kg * 994 = 7455tons to LEO.
No matter how you do the numbers for Space Shuttle, you can't match
that.
Pawel Moskalik
------------------------------
Date: Sun, 23 May 1993 16:12:12 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Moon Base
Newsgroups: sci.space
In article <C7G8GD.DL6@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <1993May22.164247.6190@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>>The more pressing question though is "Why go back to the Moon?"
>>The general public says "Been there, done that." And there seems
>>little commercial justification. There are certainly more interesting
>>scientific targets. Mars for one, minor planets and comets for others.
>
>The main reason for going back to the Moon is to start a sustained
>program of space exploration. The first step in doing that *has* to
>be convincing the public (or whoever's funding you) that one or two
>visits is not enough. A program whose support is based on "firsts"
>is headed straight for another post-Apollo disaster, because there
>just aren't that many readily-accessible "firsts". If the objective
>is sustained spaceflight, the Moon is the right place to start.
Well, which is it, sustained space exploration or sustained spaceflight?
They are different. We have sustained spaceflight now. It costs billions
and doesn't return much of value, but we have it. Selenologists would
be delighted to poke around the rocks of the Moon again and again, for
billions a pop, but is that of as much scientific value as looking at
other, more potentially promising, bodies in the solar system, some of
which are actually easier to reach?
>Commercial justification for a return to the Moon is slim, but for
>anything else -- Mars, asteroids, etc. -- it's nil.
I've been on the other side of this with Nick, but comets and Earth
crossing asteroids may offer much higher commercial rewards. And
open space offers commercial potential for communications, manufacturing,
and perhaps even power. What's Luna offer? Maybe He3, some light metals
and oxygen buried in yet another gravity well. Not very appealing.
>As for "more interesting" scientific targets, that depends on who you
>ask. There is a long list of unsolved mysteries of lunar science.
>And letting your space program be run by which target looks most
>interesting at the moment means not having a *program* at all, just
>a random grab-bag of missions.
I disagree. A program means a planned series of investigations. They
aren't required to all terminate at a single body. The Moon is a
dead world. Come back in a thousand, or a million, years, and not
much of significance will have changed. Mars, Venus, the moons of
Jupiter and Saturn, comets, all are active bodies that require
timely and continuing observation. I suggest we forget the dead
Moon, and like the pioneers crossing the western deserts to reach
the California gold fields, head for the most promising targets
first and let the desert rats comb the rest at leisure. Lunar
bases don't make economic or scientific sense, and they aren't
*necessary* stepping stones to the more interesting targets.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Sun, 23 May 1993 14:09:45 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Murdering ET (was Re: murder in space)
Newsgroups: sci.space
In article <1tjn9h$9kv@access.digex.net> prb@access.digex.net (Pat) writes:
>
>I think the Endangered Species act may apply. Also interfering with
>Diplomatic relations, and violsating the nuetrality act.
>
>pat
The Endangered Species Act wouldn't come into play for two reasons.
First ET is not listed, and second his species is not endangered by
murdering him. In fact it may be *required* under agricultural
import laws to dispose of him. It's considered environmental bad
form to import an alien species into new habitat, see rabbit (Aus),
walking catfish (Fla), certain lizards (Hawaii), tropical birds (Ga),
etc.
A diplomat has no status until his credentials are accepted by the
authorities of the country to which he is posted.
The Neutrality Act wouldn't apply unless killing ET was of material
help to a third group with which ET's species was at war.
Since ET isn't listed as a game species, even charges of hunting out
of season can't be raised. He's not listed as a songbird or a migratory
waterfowl. At best a charge of exterminating vermin without an exterminator's
license might be raised, but even that fails if the killer isn't paid for the
job.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Sun, 23 May 1993 16:00:30 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: Murdering ET (was Re: murder in space)
Newsgroups: sci.space
nsmca@aurora.alaska.edu writes:
>If I kill the dolphin and you kill me, Id have commited a minor felony
>(basically killing a protected 'animal') and you would be brought up possibly
>on manslaughter chargers. (after all I was in the act of a crime).
I should have said I was being facetious when I wrote this.
I thought that the phrase "going off the deep end" would be
an indicator.
I'd like to point out, though, that less than a hundred years (although
just barely) separate the two of us from an era where it was semi-legal
to hang someone for stealing a horse. I imagine the penalty for killing
a healthy horse in no pain was similar.
>reformat!<
>But killing a Extra-Terrestial I doubt you would be brought up on
>charges, but it is possible, depending on the current mood in the
>world and such.. and wether people knew about it.. If the ET was in
>the act of firing on you, you'd might be a HERO. You might be brought
>up on charges or atleast hated by the general populous if you killed a
>non-beligerent ET. Of course the whole matter migth be swept under the
>carpet and the common good would be maintained. That is if the ET
>family/nation did not want your hide for breakfast.
I'd like to point out that any extraterrestrial you or I see walking
down the street belongs to a civilization that could cross the
interstellar gulf; this implies a level of industry that could drop a
dinosaur killer on this planet easier than you or I could put more
gravel in our driveways.
If an extraterrestrial is walking around, vulnerable to attack, then
he is likely non-hostile. If he is hostile, then he's likely a nut
that we *could* try to defend ourselves against, just as we have the
right to defend ourselves against other humans or near-sentient creatures
on this planet (off the top of my head, great apes, whales, elephants,
and bears. Polar bears are thought to be as intelligent as gorillas by
some scientists, but since you're in Nome I won't bother to elucidate that
they're a lot more hostile).
>Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked
Where have you been the last couple weeks? Sci.space hasn't been
the same without you (although the Kill the Adsat Builders! thread
may have had something to do with it).
--
Phil Fraering |"Number one good faith! You convert,
pgf@srl02.cacs.usl.edu|you not tortured by demons!" - anon. Mahen missionary
------------------------------
Date: 23 May 1993 14:28:28 -0400
From: Pat <prb@access.digex.net>
Subject: Murdering ET (was Re: murder in space)
Newsgroups: sci.space
Unlawful discharge of a firearm, within city limits:-)??????
I guess we need to put a codicil to the Endangered species act to
include all xeno tropic life forms until otherwise unlisted.
That or define all US law to apply to sentient creatures, of course,
then we may have to start properly treating certain marine mammals.
pat
------------------------------
Date: 23 May 1993 11:41:31 -0400
From: Pat <prb@access.digex.net>
Subject: murder in space
Newsgroups: sci.space
In article <1993May18.172229.18784@bnr.ca> agc@bmdhh286.bnr.ca (Alan Carter) writes:
>
>Do the US legislators believe that their laws are superior to the law of
>the land the Americans concerned happen to be in? If not, why bother? If
>so, what are they going to do about it? What is the difference between
>passing laws that the US claims apply in other peoples' countries and
>any other form of denial of other countries' national sovereignty (eg.
>invasion)?
>
No actually, what we believe in is overlapping jurisdictions.
Your country may have whatever weak little laws it may choose,
but we will also excercise a competing claim to jurisdiction,
enforceable through either extradition and according to the supreme
court, the occasional black bag job.
You guys are absolutely sovereign to whatever degree you seem but
that does not mean we don't excercise a claim to jursidiction on acts
involving our nationals, our technology, our vessels or our property.
Besides, the english are hardly one to cry foul over wounded
national sovereignity. It's never stopped you in your history
from invading people, or trampling over their rights. Let's look
at icelandic fishing rights as local history, or the Suez.
And besides any country that still has problems with fundamental human rights
is still a bit behind.
>Sorry if that sounds aggressive, but I have had to point out to US
>citizens that I am *not* under the jurisdiction of the United States
>Supreme Court unless I happen to *be* in the United States in the
>past. I do not like having to do it. Before you c) start passing
>laws for us, you are supposed to a) invade, and b) win.
>
I thought we did, during WW2. and at teh rate yugoslavia is
broiling, we'll be in europe again fixing your mess.
>The UK computer industry has had to fight several battles over US
>invasive legislation. With all due respect to non-aggressive American
>posters,
>
Unless of course, it's our technolgy you used and licensed.
pat
------------------------------
Date: Sun, 23 May 1993 15:43:55 GMT
From: Gary Coffman <ke4zv!gary>
Subject: SDIO kaput!
Newsgroups: sci.space
In article <1993May19.172018.22512@cs.tulane.edu> boimare@rs1.tcs.tulane.edu (frank boimare) writes:
>Nntp-Posting-Host-[nntpd-22429]: rs1.tcs.tulane.edu
>Lines: 17
>
>Nixon did not end the "war." The majority of the Vietnamese people wanted to
>farm rather than die and the governments on both sides offered them a better
>chance at the latter than the former. Wars end swiftly when the people for
>whom they are being fought have no vested interest in them.
Oh dear, a bit of study of the history of the Vietnam War seems in order
for you. Perhaps you're too young to remember the sight of people clinging
to helicopters lifting from the American embassy roof. The North and the
VC very much wanted to fight to victory, and they did, crushing the South's
forces, from whom we had withdrawn material support. Nixon didn't end the
War, he found a face saving way of capitulating. The boat people are
testimony that the Vietnamese are still paying the price.
>Let's spend the money on making this world and the next few we inhabit better
>places to live. Down with war and up with space technology and exploration!
>
>(Slowly peeping out from behind a surplus heat shield...)
As well you should. :-)
Wars, and rumors of war, have been with us since Cain slew Abel. There
are roughly 50 shooting wars going on somewhere on the globe right now.
Any one of them, see Bosnia, could draw the world into conflict at any
time. As nations have found to their dismay throughout history, neglecting
defenses invites attack sooner or later. If commerce moves into space,
militarization will follow, if it doesn't lead the way. Economic activity
is the lifeblood of society, no nation can long leave it's lifeblood
unprotected.
My personal view is that space commerce won't come of age until space
dreadnaughts are cruising the spacelanes. (Likely not literally, but
the functional equivalents will be operational.)
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Sun, 23 May 1993 17:54:29 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: SDI RIP. So what happens to DC?
Newsgroups: sci.space
In article <1tgke1$7jq@usenet.INS.CWRU.Edu> ptd2@po.CWRU.Edu (Palmer T. Davis) writes:
>With space-based SDI now a thing of the past (or, more accurately, of
>the past's future :-) ), what is going to happen to programs like Delta
>Clipper and Clementine?
To a great extent, it's up to us. If we lobby for those programs they
can be kept alive. If not, they are in real danger.
Allen
--
+---------------------------------------------------------------------------+
| Lady Astor: "Sir, if you were my husband I would poison your coffee!" |
| W. Churchill: "Madam, if you were my wife, I would drink it." |
+----------------------24 DAYS TO FIRST FLIGHT OF DCX-----------------------+
------------------------------
Date: Sun, 23 May 1993 18:05:26 GMT
From: Frank Crary <fcrary@ucsu.Colorado.EDU>
Subject: Space Marketing would be wonderfull.
Newsgroups: sci.environment,misc.consumers,sci.astro,sci.space,rec.backcountry,misc.headlines
Followups set away from misc.headlines and mics.consumers
In article <C7G50C.n4F@ccu.umanitoba.ca> youngs@ccu.umanitoba.ca (Scott D. Young) writes:
>>If the proposed space station, Freedom, were built, you wouldn't
>>have any trouble making it out as a man-made object. It would look
>>like a "I", not like a point of light. Does the fact that it would
>>be a government, rather than a commercial, project mean would not
>>be disrupt the pristine sky?
> At least the science of Astronomy would benefit from a scientific
> station in orbit.
Astronomy as a scientific goal for the space station was abandoned
years ago. The scientific benefits would be for biology and material
sciences.
> ...Also, to be useful for advertising, a sign in
> space would have to be pretty bloody huge, not a "little I" as the
> space station would produce.
Not really: All advertising has to do is put the product's name into
people's mind. This can be much more subtle that having them read
the word. If people notice an "I" shaped object moving across the
sky (or have it pointed out to them) and are later told that they
were seeing (say) Intel's orbital microchip factory that would
be very good advertising: It would put the company's name into
people's heads and would connect it with something impressive.
NASA certainly hopes to get some advertising out of the space
station: Simply having a visible accomplishment moving across
the sky would help their budget enormously...
In just the same way, corporate donations to universities and
sponsorship of things like the Olympics are usefull "advertising",
even if there isn't a big sign reading "The choice of a new generation."
Frank Crary
CU Boulder
------------------------------
End of Space Digest Volume 16 : Issue 617
------------------------------