Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_4/V15NO489.TXT

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Date: Thu,  3 Dec 92 05:02:47
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #489
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu,  3 Dec 92       Volume 15 : Issue 489

Today's Topics:
                DC-1 & landing in bad weather (2 msgs)
                     Hubbles's mirror (good spin)
                 Mars: "unusual" landforms, lat/long
NASA has 5 hand grenades still on the moon from Apollo missions (3 msgs)
                           Patriot Missile
                         physiology in zero-G
                     Shuttle replacement (3 msgs)
                              spacecamp
           Terminal Velocity of DCX? (was Re: Shuttle ...)
                What is the SSTO enabling technology?

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----------------------------------------------------------------------

Date: Wed, 2 Dec 92 13:53:38 EST
From: "ZALBAR DELPHI, MAIL::GOD" <[e-mail]>
Subject: DC-1 & landing in bad weather



------------------------------

Date: Wed, 2 Dec 92 13:55:30 EST
From: "ZALBAR DELPHI, MAIL::GOD" <[e-mail]>
Subject: DC-1 & landing in bad weather

    I'm kinda curoius...
    What effect would a wind shear have on a taildown
    landing of a DC-1...

    How about cross winds...

    The whole things SOUNDS pretty workable...
    but if the DC-1 comes in on empty tanks (or nearly so),
    what if the craft has to divert to an alternate site...
    As George Carlin says,
    "The only unsceduled landing I'm afraid of is the one
     in the cornfield on the far side of the airport..."

    Which brings another point...
    Could (being realistic now) the DC-1 set down on ANY
    more or less flat surface, like a cornfield...
    Or would that result in a forest fire (er popcorn...).

===============================================================================
    Chris Sheldon
    [e-mail]
    [e-mail]
    Zalbar Delphi, Mominium
===============================================================================

------------------------------

Date: Wed, 2 Dec 1992 16:21:38 GMT
From: Pat <[e-mail]>
Subject: Hubbles's mirror (good spin)
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] (G. Scott Smith) writes:
>In article <[e-mail]> [e-mail] (Greg Wilkins) writes:
>>
>>What are the chances that hubble would have flown if the flaw in the mirror
>>was detected?
>There exists a second mirror made by another contractor.  The mirror would
>have been replaced and the mission flown.
>>
>>If there was a chance that hubble would have been grounded, maybe it is
>>better that it went up half blind (but fixable).  The science learned from
>>fixing it in orbit must also be worth something -> probably will save an
>>extra flight practising for Fred.
>If the problem had been found, it would have been fixed and the vehicle
>flown.  You don't spend several billion dollars and not fly the thing.
>Making another mirror would be cheaper than canceling the program, even
>if there wasn't another mirror already made.
>


Actually, i think they would have done what they are doing now.
ordered hughes to fix the mirror and sue them for non-performance and
charge them the extra program costs due to delays in launch.

i heard right now they are looking to sue hughes for all the money they
paid them for the main mirror.

------------------------------

Date: Wed, 2 Dec 1992 14:48:00 GMT
From: "E. V. Bell, II - NSSDC/HSTX/GSFC/NASA - (301" <[e-mail]>
Subject: Mars: "unusual" landforms, lat/long
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes...
>
>Anybody out there have the latitude and longitude coordinates of the
>"unusual" Martian landforms which have been discussed in the popular
>press in recent years?
>
>Specifically, I'm looking for the lambda and phi (Martian latitude
>and longitude) coordinates of:
>
>The "Face" in Cydonia
>and
>The "Pyramids" in Elysium
>
>(I'm writing a novel that's partly set on Mars, and I'd really like
>to know where these minor "tourist attractions" are.)
>
>Thanks in advance,
>Ken Barnes
>
>--
>*.x,*dna**************************************************************
>*(==) Ken Barnes, LifeSci Bldg.                                      *
>* \'  [e-mail]                                    *
>*(-)**Memphis,TN********75320,[e-mail]**********************
>"When I was a boy I was told that anybody could become President;
>I'm beginning to believe it."--Clarence Darrow

    I was kind of curious about this myself (what with all of the
    discussion on the net) and was able to find a reference to the
    lat/long of the "face". The position given therein is 41N,9.5.
    I examined that particular region with the Mar Digital Image
    Model (MDIM) CD-ROMs which the Mars Observer project generated
    from the Viking 1/2 orbiter data (which we distribute for the
    Planetary Data System) and found the site to be particularly
    unexciting. (I'm pretty certain that I found the "face", but
    the resolution on the MDIM CD-ROMs appears to be less than
    ideal for seeing much "detail". I suspect that it might be
    better on the original images from Viking (which we also
    distribute), but have not had the time to explore those yet.)

    I don't know the lat/long of the "pyramids", but the Elysium
    region is around 10-30N,220-260. (Somewhere in there.) Hope
    this helps.

+------------------------------------------------------------------------------+
|  Dr. Edwin V. Bell, II    |  E-mail:                       |
|  Mail Code 633.9        |    (SPAN) NCF::Bell               |
|  National Space Science    |    or   NSSDC::Bell               |
|    Data Center        |    or  NSSDCA::Bell               |
|  NASA                |    or  NSSDCB::Bell               |
|  Goddard Space Flight Center    |   (Internet) [e-mail]       |
|  Greenbelt, MD   20771    |                           |
|  [phone]        |                           |
+------------------------------------------------------------------------------+

------------------------------

Date: 2 Dec 92 08:35:58 GMT
From: Mark Sproul <[e-mail]>
Subject: NASA has 5 hand grenades still on the moon from Apollo missions
Newsgroups: sci.space

In article <[e-mail]> (sci.space), [e-mail] writes:

> Ordinary firearms wouldn't work in a vacuum anyhow.
> The gunpowder couldn't burn. The same might be true at high
> altitudes on the Earth's surface, as I've heard that in a
> particular South American city (I think it was La Paz, Bolivia),
> there's not enough oxygen in the air for them to really require
> a fire department.
>
> --KB
>

This is just NOT true. Modern firearms work in a vacuum and work underwater.
The nitro-celulose that gun powder is made from contains its own
oxygen for burning.  Even older black powder will work without outside oxygen.

When a high power rifle cartrige is set off, the chamber pressure
is in the range of 50,000 PSI.  If it required oxygen from the outside
air to get in to burn, the oxygen just could not get in if it wanted
to.  The chamber is COMPLETLY sealed, or if it wasn't that high pressure
would escape, injuring the shooter.

Mark Sproul
High Power Rifle Competitor
Member of NJ State Rifle Team

-----------------------------------------------------
Mark Sproul - KB2ICI - New Jersey
[e-mail]

------------------------------

Date: 2 Dec 92 05:00:47 GMT
From: [e-mail]
Subject: NASA has 5 hand grenades still on the moon from Apollo missions
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Patrick Draper) writes:
> In article <[e-mail]> [e-mail] writes:
>>
>>Ordinary firearms wouldn't work in a vacuum anyhow.
>>The gunpowder couldn't burn. The same might be true at high
>>altitudes on the Earth's surface, as I've heard that in a
>>particular South American city (I think it was La Paz, Bolivia),
>>there's not enough oxygen in the air for them to really require
>>a fire department.
>>
>>--KB
>>
> Of course ordinary firearms will work in a vacuum.
>
> [Brief elementary physics lesson deleted.]
>
> ------------------////////////////////\\\\\\\\\\\\\\\\\\\\------------------
> | Patrick Draper           Disclaimer:  I can't control my fingers,        |
> | [e-mail]                   I can't control my toes! - Ramones |
> | University of Michigan Computer Club                                     |
> NO CARRIER                     We are a nation of laws, not people         |
> ------------------\\\\\\\\\\\\\\\\\\\\////////////////////------------------

Excuse me. Didn't mean to start a flame-fest on the nature of
flame/explosions in a vacuum. I'll be more careful where I play
with matches in the future.

As for the part about the city at high altitude, please note that
I didn't say that flames were not possible, it's just that they were
said to propagate at such a slow rate that they are readily
extinguished.

Thanks for the correction. Have mercy.

--
*.x,*dna**************************************************************
*(==) Ken Barnes, LifeSci Bldg.                                      *
* \'  [e-mail]                                    *
*(-)**Memphis,TN********75320,[e-mail]**********************
"If nobody said anything unless he knew what he was talking about,
a ghastly hush would descend upon the earth."--Sir Alan Herbert

------------------------------

Date: 2 Dec 92 16:54:23 GMT
From: Robert Mitchell <[e-mail]>
Subject: NASA has 5 hand grenades still on the moon from Apollo missions
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
....

>Ordinary firearms wouldn't work in a vacuum anyhow.
>The gunpowder couldn't burn. The same might be true at high
>altitudes on the Earth's surface, as I've heard that in a
>particular South American city (I think it was La Paz, Bolivia),
>there's not enough oxygen in the air for them to really require
>a fire department.
>
>--KB
>
I do not really believe this; combustion starts in an air-tight cartrige.
This causes the case to form an air tight seal in the chamber,
and the slug to form an air tight seal in the barrel.
Outside oxygen does not have much chance to participate.
It would seem that any oxygen required for combustion
would be part of the formulation.
I would think that you would get a much higher muzzle velocity
with no air to push down the barrel...
 - Robert Mitchell
--
UUCP:  [e-mail]
DDD:   408-746-8491
USPS:  Amdahl Corp.  M/S 205,  1250 E. Arques Av,  Sunnyvale, CA 94086
BIX:   bobmitchell

------------------------------

Date: 2 Dec 92 16:18:44 GMT
From: Titch <[e-mail]>
Subject: Patriot Missile
Newsgroups: sci.space

[e-mail] (Brian Weaver) writes:
> What was completed previous to the Gulf War was a new
> antiballistic version that had a new guidance system capable of
> intercepting another missle in flight.

Probably. :-)

Rich.
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Rich Browning ([e-mail])   * The Intel Plentium: Ethernet controller
Department of Computer Science    * or fiendish knitting pattern?
University of Brighton            * What!? It's a PROCESSOR???
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

------------------------------

Date: 1 Dec 92 10:05:35 GMT
From: Magnus Olsson <[e-mail]>
Subject: physiology in zero-G
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:
>
>>From: [e-mail] (Magnus Olsson)
>Newsgroups: sci.space
>Date: 29 Nov 92 23:17:18 GMT
>Organization: Theoretical Physics, Lund University, Sweden
>
>-[General discourse on why it's a good idea to wear clothing while operating
>-a blender or a circular saw.]

John, if you're going to flame someone (albeit flippantly), you should at
least observe the common courtesy of getting your attributions right, and not
deliberately distort what people say. I hope I'm wriong, but I get the
feeling that you're trying to make it seem as if I had written
something highly inappropriate. If that is so, then *please tell us*
what is inappropriate, and why, don't just imply it.

For new readers: I don't know really *what* John is trying to imply
that I meant, but somebody else had been speculating about the need
for female astronauts to wear supportive clothing (bras or special
jump suits) in zero-g, and I made a HHOS ("ha ha, only serious")
comment that NASA probably had done speical research on this.

>I presume you've read "Rendezvous with Rama".

Yes, I have, several years ago. What has that got to do with it?


>So - when is Sweden going to buy a Shuttle flight and make some of the
>movies it's famous for, but in zero-G? And is your research the groundwork
>for such an undertaking? :-)

You know, we Swedes are getting sick and tired of hearing that kind of
remarks, even with smilies attached. I can assure you that they have
long since lost any relevance. Nowadays, they must be said to belong
to the same kind of ethnic slurs as stories about sausage-eating,
war-mongering Germans with scars and heavy Prussian accents. But it's
of course very easy for you Americans - who, if one were to judge by
American pop. culture, and the postings here on Usenet, seem to be
the most sexually obsessed people on Earth - to have somebody to point
your fingers at, isn't it?

Sheesh.

(Oops - I seem to have made an ethnic slur myself. Sorry for that -
please note the wording "if one were to judge by ... seem", and that I
certainly don't mean *all* Americans)

              Magnus Olsson                | \e+      /_
    Department of Theoretical Physics      |  \  Z   / q
        University of Lund, Sweden         |   >----<
 [e-mail], [e-mail]  |  /      \===== g
PGP key available via finger or on request | /e-      \q

------------------------------

Date: Wed, 2 Dec 1992 12:27:44 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Shuttle replacement
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>
>the three year hiatus was vital for fixing numerous problems, many of which could have led to total loss of the shuttle.   now if this were an
>experimental test program, you push on.  The X-15 was losing aircraft/space
>craft.  they were killing pilots,  they were having major problems,  but it was an   experimental research program.
>losing a shuttle with the HST would have been an unmitigated disaster.
>losing the CGRO would have been a disiaster.  lsoing galileo would have
>been a major problem.   Cargo carrying,  crewed  semi-operational
>vehicles would have been a major problem.......

Yes, the real crime was treating Shuttle as an operational system after
so few flights. No commercial aircraft would be certified operational
after so few takeoffs and landings. Shuttle is still significantly
more risky than any operational aircraft, yet we fly it now. My point
is that the incremental risk for flying it with some of the potential
problems unfixed may not have been that much higher than the risks
it endures now, after the fixes.

>Gary  i think you should study under what conditions risk is applied,
>before you grandly declare it was a risk averse america.
>Remember,  we ground entire airline fleets and military birds when
>problems are detected and fixes are applied.  the AH-64 spent half its
>life until 1988 grounded for one problem or another.  the F-14s spent
>months flying under restricted conditions because they kept stalling
>and falling into the water.  the DC-10 spent months grounded after
>chicago.  they forced groundings of 747s pening emergency inspections
>of cargo hatches after the UAL problem..... operational aircraft are
>always restricited until they know and understand the problem.  we dont
>want anymore comets.

This is all true too. But *when necessary* military aircraft do fly
without the fixes. The losses are accepted as part of the cost of
getting the mission done. Shuttle grounding, at a time of Titan
troubles put national security at risk. I think we were down to
our last KH-12. A lot of money was spent, and a lot of time was
used to fix numerous *potential* problems as well as the proximate
problem. The question is whether these potential risks were sufficient
to offset the costs to the missions of the delays incurred. Normally
when an aircraft is grounded, there are alternatives available so that
the mission can continue. At the time of the Shuttle grounding, there

was no alternative for many payloads. There still isn't in some cases.
One failure seems insufficient to cause a total halt in space launches
when the previous record was 100% successes. Being risk averse isn't
bad, but being too risk averse can be. There's such a thing as carrying
zero failure tolerance too far.

Gary

------------------------------

Date: 2 Dec 92 16:35:47 GMT
From: "Michael V. Kent" <[e-mail]>
Subject: Shuttle replacement
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>
>What's the height/width of the projected DC? What I'm asking is how
>stable is this thing on just wheels? Would a bracing structure be
>helpful or required when moving it over ordinary rough concrete surfaces?

From the SSTO fact sheet I picked up at the Northeast Space Developemnt
Conference:

                          DC-X                DC-Y
                          ----                ----
Empty Weight:           22,760 lb          104,100 lb
Gross Liftoff Weight:   41,630 lb        1,279,000 lb
Vehicle Height:             39 ft              127 ft
Width at Base*:             11 ft               40 ft

* My estimates based on the listed height and drawings of both vehicles.  There
is no guarrantee that the drawings are to scale.

Mike

--
Michael Kent              [e-mail]        Rensselaer Polytechnic Institute
"Interviewing during a recession is a lot like faking an orgasm.  You have to
pretend you're interested all the while getting badly screwed." - Anonymous
Tute-Screwed Aero, Class of '92                               Apple II Forever!

------------------------------

Date: 2 Dec 92 17:30:00 GMT
From: [e-mail]
Subject: Shuttle replacement
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Allen W. Sherzer) writes...
>In article <qg#[e-mail]> [e-mail] (Greg Moore) writes:
>
>In ten years of operation this is the first year where Shuttle has gotten
>even close to projected flight rates.
>

So than now as the system has matured and the probabiltiy of launching when
they say they will has been reached, you want to kill the system. Also the
cost reductions that are now being implemented that will reduce further the
cost of launch you want to throw away. Makes a lot of sense Allan

>>However, if something DOES go wrong, or for some reason you want a
>>person on sight, then the shuttle wins.
>
>Maybe even not then. It depends on the cost of failure.
>
The cost of failure for communications satellites is not simply measured
by the cost of the hardware and launch vehicle. Intelsat was willing to
pay the big bucks to NASA to retrieve I VI because it would take over two
years longer to build a new sat and get it in the air. During that time they
would lose hundreds of millions of dollars in revenue. Therefore Allan old
boy please add the cost of the loss of revenue, both in actual dollars lost
as well as the permanent loss in market share to other satellite vendors.

>>For something like Hubble, or
>>some other unique satellites, I'd prefer the Shuttle.
>
>One reason Hubble is unique is that Shuttle eats almost a third of
>NASA's budget. I hope you consider this when measuring Shuttle utility.
>

Got any idea what you mean by this remark? You sure as heck could not have
gotten HST up to that altitude with anthing less than NLS II or Shuttle


>If YOU where paying for Hubble, which would you pick?
>

I would pay the trucking company that could get it to the orbit that I want.

>>    Allen, they haven't made a profit in 6 years (since Challanger).
>
>Largely because they are forced to compete with government subsidized
>competition.
>

No Allan if you remember no commercial sats are going up on the Shuttle.
Where is this government competition? The reason is that MacDac offered a
ver low price to uncle air force that is below manufacturing costs. Then
to recover a profit they added a clause that if the first 18 flights of
GPS (which is a government contract that MacDac follows you magic formula)
are successful MacDac gets a col 72 million. Well they have almost made it.
the first 17 have made it to orbit, but MacDac chickened out. They negotiated
for a lesser amount for 12 successful launches. Made much less money than
they would have. No guts no glory I guess.

From the info I have the Delta II line would shut down without the government
that you detest so much not paying for GPS on a regular basis.

>The point still remains that the commercial providers are REDUCING the
>cost of access to space; Shuttle increases it. Commercial launchers spend
>investors money, Shuttle spends MY money. Given a choice between a cheaper
>option which costs me nothing and a more expensive one I need to pay for
>I would pick the former. How about you?

No as I have just pointed out, any of the American launchers including the
Delta II, Atlas II, and Titan III, IV and V, depend on the government dole.
If that market went away we would have a lot of rusting machinery that used to
be called rockets.

>
>>>But what would have happened if we developed a commercial based infrastructure
>>>back in 1980? Much furthur I'll bet.
>
>>Let's argue today, not the past.
>
>One thing we need to do to make progress is understand the mistakes of
>the past and then have the courage to correct them.
>
What we need to understand is that this whole industry is still in an infantile
stage that REQUIRES the input of government funds to survive. It is all of
our hopes that the money spent can be used to fund the developemnt of truly
low cost access to space, of which the DC series is one end of the spectrum.
You have not even addressed the other end, the HLV end of the spectrum. IT too
will depend on the influx of government cash until we develop a commercial
space industry, either in products or raw materials. Communications is making
a good first stab at the former market, we need to return to the moon to foster
the second, and in the end, far larger market.

Ad Luna, Per Ardua
Dennis, University of Alabama in Huntsville

------------------------------

Date: Wed, 2 Dec 1992 14:35:00 GMT
From: [e-mail]
Subject: spacecamp
Newsgroups: sci.space

Would someone please Email me the standard stuff on the Astronaut Camp in FL.
        Thanks, Karl   ([e-mail])

------------------------------

Date: Wed, 2 Dec 1992 12:11:10 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>
>Now i know this would make gary coffman happy, no more blazing balls of
>ROCKET FUEL crashing into DISNEYLAND!!!!!!  so maybe we should compromise
>system design, throw away the manueverability to SHUT UP GARY.

Chutes add mass for the chute, suspension, and hard points. They aren't
cheap. And they aren't 100% reliable (but then what is?). To shut me
up, all you need to do is agree to launch and land this thing away from
major population centers. It's not an airliner, and it likely can never be
an airliner. If it's a cheap launcher that ocasionally crashes or goes
boom in an uninhabited spot, that's good enough for me.

Gary

------------------------------

Date: Wed, 2 Dec 1992 15:12:42 GMT
From: Brad Whitehurst <[e-mail]>
Subject: What is the SSTO enabling technology?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] writes:
>
>>>According to the assessment of SSX done by the Aerospace Corporation, it
>>>is now possible dur to slight improvements in the specific impulse of
>>>engines and some new lighter materials.
>
>>You might want to back off the ISP statment there Allan.
>
>Well it wasn't *MY* statement, it was the Aerospace Corporation.
>
>>You can't beat the ISP of the SSME
>
>The RL-10-a4 is just as good as the SSME. the RL-10C1 (if built) will have
>about 15 seconds higher ISP than the SSME.
>
>>and even if you get close you are going to have heap
>>big problems keeping any kind of reusablility of the engines.
>
>RL-10s seem to do just fine.
>
    But are they reused?  Also, I don't know specifics of the SSME
per se, but one of our labs did the spectral vibration analysis of the
data tapes from SSME turbopump tests years ago, when they were
exploding with distressing regularity.  I'd guess the pumps are always
going to be a weak link, especially when you are trying for high
performance/low weight (a la spacecraft, F1 racers, etc.).  Rotating
equipment is always tricky at the margins!  BTW, does anyone know if
the SSME turbopumps are supercritical rotors?  If so, how many
criticals do they go through?
--

Brad Whitehurst    |   Aerospace Research Lab
[e-mail] |   We like it hot...and fast.

------------------------------

End of Space Digest Volume 15 : Issue 489
------------------------------