Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_383.TXT

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Subject: SPACE Digest V8 #383

SPACE Digest                                      Volume 8 : Issue 383

Today's Topics:
              Re: Why no aliens
         Re: Are we ready for terraforming???
           New Rockets? No Hurry, OTA Says
           Re: Watching Shuttle Land at Edwards AFB
                   Re: SDI
           Re: access to space; how to deny
            Re: Shuttle names--old and new
   Re: Unmanned w/old SRBs (was Re: space news from July 11 AW&ST)
                 Re: Phoenix
----------------------------------------------------------------------

Date: 12 Sep 88 04:38:49 GMT
From: ndsuvax![e-mail]  (Peter Kinsella)
Subject: Re: Why no aliens

In article <[e-mail]>, [e-mail] (Ralph Hand) writes:
> Why bother trying to kill it.  We just land, one of our diseases goes
> rampant through their population presto we have control of our first
> new world.  (Sort of like the Spanish in South America, or any of the
> hundreds of other civilzations wiped out in that period).

     In order for one of our diseases to harm an alien, our bioligical
structures would have to be very very similiar.  For example, humans
are hardly, if at all, affected by a disease that affects fish. This is
true for a multitude of diseases that exist in our own world. The odds
of one of our diseases harming an alien race must be extremly high.

     Pete Kinsella

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

Date: 14 Sep 88 00:22:32 GMT
From: [e-mail]  (Jim Giles)
Subject: Re: Are we ready for terraforming???

From article <[e-mail]>, by [e-mail] (Mark Biggar):
> In article <[e-mail]> [e-mail] (Mike Trout) writes:
>>> > >(Jim Giles) writes:
>>> > Well, it does appear that a single asteroid hitting Australia wiped
>>> > out the dinosaurs.

Besides, I didn't write that!  In fact, I've now forgotten who did.

J. Giles
Los Alamos

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

Date: 12 Sep 88 07:10:40 GMT
From: mcvax!enea!erix![e-mail]  (Howard Gayle)
Subject: New Rockets? No Hurry, OTA Says

From Science, 5 August 1988, pp 647-8:

Unless the United States wants to send people to Mars or deploy
a space defense system, it can get by with incremental
improvements in space transportation, according to a rocket
buyer's guide.

A note of sobriety has crept into discussions of the US space
program, and it has come from a surprising source---Capitol
Hill.  On paper, at least, Congress seems to recognize that the
new austerity in government means there is no room for false
starts.  Decisions made in the next 2 years will set a course
for space policy for the rest of the century.

The latest sign of realism can be found in a report from the
Office of Technology Assesment (OTA), billed as a "buyer's
guide" to launchers, released on 27 July ("Launch Options for
the Future: A Buyer's Guide").  It was commissioned by the
House subcommittee on space applications, chaired by Rep. Bill
Nelson (D-FL)...

[P]lans to deploy a space-based strategic defense or to send
humans to Mars, would sharply increase transportation needs.
These are over and above the 19 shuttle flights required for
assembly of the space station, due to be in orbit by 1997.
Thus, estimates of demand range from a low-growth requirement
of 600,000 pounds launched to low earth orbit each year to
4 million pounds per year...

Three things became clear immediately, says study director
Richard DalBello.  First, the current fleet cannot begin to cope
with the demands of a trip to Mars or a major military
deployment.  Perhaps with a rapid investment in new
transportation systems, the US could mount a Mars mission or
SDI---but not both.

Second, if there is no rapid increase in the pace of launching
(that is, no SDI or Mars trip), the economic issues are of
minor importance.  An entirely new rocket fleet would not be
much cheaper than what exists now.  This is because the
development costs are about equal to the savings that would be
gained in transportation...

Third, if it seems important to break with the past and
increase the launch rate, it will be necessary to invest in new
technology.  OTA did not single any out as especially promising.

The most striking conclusion, therefore, is a conundrum.  There
will be no economic payoff from new delivery systems such as
the Air Force's "Advanced Launch System" unless the government
at the same time decides to put the system to full use.  And
putting it to full use means buying a big package to be
delivered, such as a Mars trip or SDI.

Even under the most favorable circumstances, the savings of a
new system may be illusory, for the money "saved" in making
each flight cheaper will be "lost" on buying an increased
number of flights.  It will also be lost on buying the payload...

Another conclusion...is that the present fleet is fairly well
suited for the agenda that NASA has laid out for itself.  Even
without major improvements existing rockets should be able to
lift 860,000 pounds into orbit per year, compared to 400,000
pounds on average between 1980 and 1985..."[B]y improving
existing vehicles and ground facilities and buying more launch
vehicles, the US could easily increase its launch capabilities
to 1.4 million pounds...per year."   This "enhanced" low-growth
approach would more than double the 1985 capacity, and produce
enough to "support a space program with slow growth for many
years."  It could be done by slightly increasing the capacity
of some ELVs, improving the shuttle's booster rockets, testing
and possibly developing liquid boosters, using a lighter
shuttle fuel tank, making ground operations more efficient,
building another Titan launch pad, and using more automated
production and processing facilities.

The entire "life cycle" cost of this approach would be $110 to
$120 billion between now and 2010.  For about the same price,
but with greater risk, according to OTA, Congress could invest
in one of several "transition vehicles."  Included in this
category are an unpiloted cargo version of the shuttle called
shuttle-C, a greatly improved Titan rocket, or an entirely new
system based on an interim version of the Air Forces Advanced
Launch System.

If Congress decides to go ahead with construction of the space
station next year, it might be worth buying shuttle-C just for
that purpose.  Its capacity is twice that of the shuttle, and
it could reduce station assembly flights by 7, cutting costs by
$1.7 billion.  According to NASA, that savings would more than
pay for shuttle-C.  But, OTA notes, NASA may well have
underestimated...

An incisive report by the Congressional Budget Office in May
points out that transportation and other "infrastructure" costs
already swallow the lion's share of the civilian space budget
("The NASA Program in the 1990s and Beyond").  Playing out
NASA's existing programs will require large expenditures
through the end of the century.  According to this estimate,
NASA's total budget must grow from $9 billion in 1988 to $16.4
billion in 2000 (constant dollars) just to cover the
committments already made.  NASA had a terrible struggle
climbing the first step in this long staircase this year,
moving its budget up from $9 billion to $10 billion.  It seems
unlikely therefore that there will be room for any radical new
departure in space transportation, unless something already on
the books is dropped.
---Eliot Marshall

[Flames to Richard DalBello at OTA.]

Howard Gayle
TN/ETX/TX/UMG
Ericsson Telecom AB
S-126 25 Stockholm
Sweden
[e-mail]
{mcvax, uunet}!enea!ericsson.se!howard
Phone: [phone]
FAX  : [phone]
Telex: 14910 ERIC S

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

Date: 9 Sep 88 18:05:19 GMT
From: aero!venera.isi.edu![e-mail]  (Craig E. Ward)
Subject: Re: Watching Shuttle Land at Edwards AFB

In article <[e-mail]> [e-mail] (Dan Allen) writes:
>Does anyone know the scoop on being able to go on base at Edwards AFB
>for the Shuttle landing in October or whenever it is going to land?  I
>went to a landing in 1982 there but did not make any of the details.  I
>have heard a rumor that the public is not allowed on base any more for
>landings.  Any truth to this rumor?
>
>Dan Allen
>Apple Computer
>[e-mail]

The California chapters of the National Space Society (NSS), cooperating
through the California Space Development Council (CSDC) are planing to
attend the landing at Edwards.  In Northern California contact Tim Kyger
of the San Francisco Chapter evenings at [phone] (This number is
published in the Spacefaring Gazette without an area code; I am assuming
it is 415.)  For Central and Southern California contact me by email.  I
am with OASIS, the Los Angeles and Orange Counties chapter of NSS.

(We have a coordinator for this but I don't want to publish his number
without asking him first.  Kyger's number was published already so I
assume it's okay to distribute it here.)

        Craig

--
====================================================================
ARPA:     [e-mail]
PHONE:    [phone] ext. 111
USPS:    USC Information Sciences Institute
    4676 Admiralty Way, Suite 1100
    Marina del Rey, CA 90292
Slogan:    "nemo me impune lacessit"
====================================================================

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

Date: 10 Sep 88 05:52:41 GMT
From: amdahl!ems!viper![e-mail]  (David Messer)
Subject: Re: SDI

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
 >In article <[e-mail]> [e-mail] (Kian-Tat Lim) writes:
 >>Something that has been bugging me throughout this "denying access to space
 >>via Stinger" discussion.  How much is the warhead of a shoulder-fired weapon
 >>going to disturb an SSME/Ariane/whatever, considering that the hottest target
 >>is the exhaust plume?  With all that energy spewing out, it would seem to me
 >>that the extra "bump" from a 50-pound explosive (to be generous) would be
 >>negligible.
 >
 >shoulder-launched weapons don't pack that much explosive, but it's still
 >nothing you want to be standing near when it goes off.

The Stinger has about a 7 lb warhead.

The main reason that shoulder launced weapons aren't a real
worry is that they have only about a three-mile range (and
probably a maximum altitude of 5000 ft or so, although I don't
have the figures handy).  To hit the shuttle, you would have
to be quite close -- in the area that is checked repeatedly
for intruders.

A much more likely scenario is someone machine-gunning the
thing a couple of days before launch.
--
If you can't convince |   David Messer - ([e-mail])
them, confuse them.   |   Lynx Data Systems
   -- Harry S Truman  |
                      |   amdahl   --!bungia!viper!dave
                      |   hpda    /

Copyright 1988 David Messer -- All Rights Reserved
This work may be freely copied.  Any restrictions on
redistribution of this work are prohibited.

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

Date: 9 Sep 88 20:55:21 GMT
From: attcan!utzoo![e-mail]  (Henry Spencer)
Subject: Re: access to space; how to deny

In article <[e-mail]> [e-mail] (Larry Wall) writes:
>How much disparity in thrust can the stack put up with?

I think it's something like 2-3%.  There has to be some compensation for it
because the solids are not throttlable and there is no way to guarantee
that their thrusts will be precisely equal.  (Some precautions are taken
to minimize imbalances, such as using segments from the same batch to
build both SRBs for each mission.)  In particular, some imbalance at burnout
is to be expected.

>Can the hold-down bolts keep the thing from taking off if one SRB fires and
>the other doesn't?

The hold-downs are blown simultaneously with SRB ignition, so this isn't
possible.

>What would be the effect of a well-timed model airplane with a zip gun putting
>a tracer bullet into the ET as it was lifting off?

It would have to be a pretty stealthy design to get that close without being
spotted.  That aside, it might get messy; the ET walls are thin.
--
NASA is into artificial        |     Henry Spencer at U of Toronto Zoology
stupidity.  - Jerry Pournelle  | uunet!attcan!utzoo!henry [e-mail]

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

Date: 10 Sep 88 02:57:21 GMT
From: jato![e-mail]  (Jordan Brown)
Subject: Re: Shuttle names--old and new

In article <> [e-mail] (Henry Spencer) writes:
>In article <> [e-mail] writes:
>>... Supposedly either "Challenger" or "Atlantis" was the name of
>>Tom Swift's rocket, but I've never been able to track that down for sure...
>
> Tom Swift Jr's 1950s rocket ship was the Star Spear...

You are correct.  The Star Spear was his rocket.  The moon ship (from Tom
Swift in the Race to the Moon - #12) was named Challenger, and had a
repelatron drive.  It was in general a much better ship.

Important stuff, eh?  Must be some reason I collect it...

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

Date: 10 Sep 88 15:04:14 GMT
From: phri!dasys1![e-mail]  (Tom Neff)
Subject: Re: Unmanned w/old SRBs (was Re: space news from July 11 AW&ST)

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
> ... possibly the most likely way to lose an orbiter is a landing
>accident, which might well leave crew and payload intact but damage the
>orbiter badly enough to make it unflyable.

Thank you for pointing this out, I really wasn't taking nonfatal
"totallings" into account but it's nice to think about ANY kind of
shuttle accident (if we are indeed fated to have them) where the crew
is OK.

>Then, as I said, we must send them to the Smithsonian at once.  No matter
>how careful you are, you cannot fly them without taking risks.  If we keep
>on flying them, even just our present little fleet, losses are inevitable.

The point you are missing is that your proposed "remedy" is equal in
severity to the worst consequences of leaving things unremedied.  In
other words, if an accident is SOMEDAY inevitable and if such an
accident would put the remaining orbiters in the Smithsonian for you
anyway, then why jump the gun and do the future accident's work for it
immediately, without getting some orbital missions in there first.
Just doesn't make sense.  (Flight 25's disaster was horrendous, but even
it could not erase the manifest for the previous 24 flights!)

You are proposing a dichotomy: go back to the old pre-1986 practices or
shut everything down immediately.  I am saying there is a middle ground:
proceed, but more conservatively.  Strapping those old SRBs onto our tiny
remaining fleet, even unmanned, is just asking for trouble.  (Tough to
remember but that's what got this conversation started. :-) )  We both
agree trouble is inevitable eventually, but I insist we can and should
increase the odds in our favor whenever we have a chance.
--
Tom Neff            UUCP: ...!cmcl2!phri!dasys1!tneff
    "None of your toys    CIS: 76556,2536           MCI: TNEFF
     will function..."    GEnie: TOMNEFF           BIX: t.neff (no kidding)

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

Date: 10 Sep 88 23:27:38 GMT
From: attcan!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Phoenix

In article <[e-mail]> [e-mail] writes:
>>"It is no argument to say that launch vehicles are more complex
>>devices than, for example, an F-15 or 767.  Clearly they are not.
>
>Is this true?  It doesn't appear clear to me, I'm afraid! ...
> [comments about the empirical nature of engine design]

Hudson is talking about sheer mechanical complexity, not difficulty of
design.  Look at one of the see-through drawings of an aircraft that
journals like Flight International routinely publish; the complexity is
mind-boggling, especially for high-performance military aircraft.
Just the number of *moving* parts is enormous.
--
NASA is into artificial        |     Henry Spencer at U of Toronto Zoology
stupidity.  - Jerry Pournelle  | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V8 #383
*******************