Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_2/V11_268.TXT

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Subject: SPACE Digest V11 #268

SPACE Digest                                     Volume 11 : Issue 268

Today's Topics:
          Re: Pegasus launch from Valkyrie  (or ...
              Re: Fermi Paradox
         space news from March 5 AW&ST, etc.
               Re: Interstellar travel
              Re: National Space Society
         NASA Headline News for 04/13/90 (Forwarded)
        Re: Interstellar travel and the Fermi paradox
----------------------------------------------------------------------

Date: 15 Apr 90 23:54:57 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Pegasus launch from Valkyrie  (or ...

In article <[e-mail]> [e-mail] (Mary Shafer (OFV)) writes:
>The only drawback I see at first glance is that the B-58 is too close
>to the ground.  The gear wouldn't touch if there was a Pegasus under
>the wing.

Surely Pegasus would go in place of the B-58's bomb/fuel pod, under the
fuselage, not under a wing?  The bomb pod was both longer (62ft) and
fatter (7-8ft) than Pegasus, and it weighed about as much (40klbs) at
takeoff, although drop weight was about half that and some work would
be needed to qualify the B-58 for dropping Pegasus.  Clearance for the
Pegasus wing between the inboard engines looks adequate at first glance,
although I don't have B-58 drawings and it isn't a large aircraft.  You
might have to fit a slot in the fuselage for Pegasus's tailfin (if OSC+H
ends up using a Tristar for commercial launches, such a slot will be
needed in it).
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 16 Apr 90 00:02:09 GMT
From: snorkelwacker!usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Fermi Paradox

In article <[e-mail]> [e-mail] (Frank Scherb) writes:
>Why not consider the idea that the Galaxy is so big that given about
>a million years of exploration you still only see a very small piece
>at best? ...

Exploring from a central point, this would be true.  But it shouldn't
take more than a thousand years at most for a major colony to become
a starfaring civilization itself.  If we figure major colonies ten
light-years apart, and assume travel time is short compared to the
thousand-year buildup time, that's a light-year per century, or
about ten million years to cross the galaxy.  There's been plenty
of time for that; the galaxy is old.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 16 Apr 90 01:05:43 GMT
From: clyde.concordia.ca!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from March 5 AW&ST, etc.

USAF issues RFP for initial design work on converting the Vandenberg
shuttle pad for Titan 4.  (The USAF wanted to build a new Titan pad,
but Congress told them to investigate using the shuttle pad first.)

Ariane pieces being recovered, failure investigation underway.  Looking
at the telemetry, it seems water flow to one of the main engines was
cut off.  (The water is used to regulate combustion pressure.)  There
has been one past case of a momentary drop in engine pressure thought
due to interruption in water flow.  This time, at T+6.2s, chamber pressure
of one main engine dropped from 58 atmospheres to 30 atmospheres quite
abruptly, and stayed there.  The guidance system gimballed the other
engines to compensate, but as speed and acceleration built up, they
had to gimbal further and further.  At about T+90s, they hit their
stops.  The unbalanced thrust started to turn the booster sideways,
and it quickly broke up under the aerodynamic stresses.  The range
safety officer then triggered the destruct system to be sure that the
launch was completely destroyed.  There was some concern about the cloud
of toxic fuel vapors resulting from the explosion, but it was blown out
to sea and caused no problems.

Arianespace is basically assuming that the interruption in flights will
be short, and is still signing customers for new launches and building
Arianes at full production rate.  The next mission probably will be
delayed several months.  It was meant to go up April 3, carrying a pair
of European comsats.  The first and second stages of the Ariane for that
mission, and its strap-on boosters, were assembled and are being held
in the vertical assembly building at Kourou.  The satellites similarly
had arrived and are in storage at Kourou.

One real concern that has been raised is that the failing Ariane passed
within about 2m of the top of the umbilical mast, because the ailing
engine was the one closest to the mast.  The exhaust struck the mast,
in fact, although damage was minimal and repairs will not be a problem.
The trouble is, if the booster had *hit* the mast, it and 420 tons of
fuel could have crashed back down onto the pad.  A working group is
looking at pad hardening and what would be involved in rebuilding it
after a major pad accident.  [Score one successful prediction for me:
a year or so ago I said that Arianespace would regret being dependent
on a single operational pad.  They are now taking that vulnerability
a bit more seriously...]

Arianespace's tenth-anniversary celebrations, set for March, will be
postponed!

Arianespace is unhappy about the commercial implications.  It has been
trying hard to establish itself in the Japanese market, and both of the
destroyed comsats were Japanese.  Competition is getting stronger, and
although most of Arianespace's competitors formally expressed sympathy,
privately there were few tears:  customers are suddenly more interested
in hedging their bets, and inquiries are up.  There is also a definite
possibility that Japan will boost funding for development of its own
H-2 launcher.

The insurers say this is the biggest loss in history, although recent
launches have generally been successful, the industry is healthy, and
insurance rates have been slowly dropping from their all-time peak in
1986 (a very bad year).  Rates probably won't rise, but they aren't going
to fall much in the near future.

Atlantis launches AFP-731 spy/snoopsat, after repeated delays due to
weather and minor problems.  The launch was visible along much of the
US Atlantic coast due to the very high orbital inclination.

Pictures of the Gamma Ray Observatory, which has been delivered to NASA
for launch in November.  The launch was originally set for June, but
slipped in the latest shuttle shuffle.  The experimenters are impatient
because they would like to get GRO up as soon as possible to observe the
current solar-activity maximum and the evolution of supernova 1987A.
GRO has been a bit of a construction challenge because the large size
of sensitive gamma-ray instruments has produced a big, dense, heavy
spacecraft.  (One aspect of this has been careful planning for the
eventual reentry, since quite a bit of it will survive to impact.)
Expected orbital lifetime is eight years, given a high-altitude shuttle
launch to minimize fuel consumption.  GRO also is built for on-orbit
refueling, although there are no firm plans to use this.

Inmarsat awards a study contract for a system to monitor the health of
Navstar and Glonass navsats and transmit updates on malfunctions via
Inmarsat's comsats.

[From Flight International, 7 Feb:]

Pictures of various upgraded Delta configurations that McDonnell Douglas
is studying, in particular to try to make Delta hefty enough to compete
with Atlas-Centaur.  The first one, already being marketed, will have an
oxyhydrogen second stage using a single RL-10 [Centaur uses two], plus a
fatter payload fairing.  The second would fatten and lengthen the
oxyhydrogen stage and fatten the payload fairing still further; the thing
looks topheavy.  The final two configurations use a pair of Delta first
stages strapped together [!], solid strap-ons clustered around the base,
with either a stretched version of the current second stage and a PAM-D
third stage, or the fat oxyhydrogen second stage.

Feature article on the Medilab module that will go up to Mir sometime
this decade, to provided dedicated facilities for studying long-term
effects of free fall, for use by pairs of specialist medical cosmonauts.

[Flight International, 21 Feb:]

Iraq claims plans to launch two types of indigenous non-military satellites
for scientific purposes, date and launcher unspecified.  The launcher is
likely to be the Abid three-stage rocket which flew a suborbital test in
December; its capabilities are probably similar to Israel's Shavit.

[Flight International, 28 Feb:]

Visual inspection of LDEF turned up many micrometeorite/debris craters,
some substantial.  Atomic-oxygen erosion was serious, especially in the
mounting material of four solar-cell modules on LDEF's leading face:
one was gone, one floated away during retrieval, the third was picked
off the bottom of the payload bay after landing, and only one stayed
put throughout.  Copper and silver coatings had oxidized, to the point
where thin ones often disappeared completely.  Paint samples had been
darkened considerably by ultraviolet.  A micrometeorite collector lost
most of its thermal blanketing to oxygen erosion.  A particular puzzle
is discoloration of "reflecting materials such as Teflon" [I assume
they mean Teflon coated with something].
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 13 Apr 90 16:04:15 GMT
From: cs.utexas.edu!uwm.edu!ogicse!blake![e-mail]  (Gregory Milligan)
Subject: Re: Interstellar travel


    I'm sure that people tried to discourage Columbus with much
the same arguments (with obvious adjustments for available technology,
of course).

Greg Milligan

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

Date: 13 Apr 90 05:21:17 GMT
From: agate!agate![e-mail]  (William Baxter)
Subject: Re: National Space Society


Posted for Jim Bowery.  Please direct responses to him.

William Baxter
-----------------------------------------------------

Date: Tue, 10 Apr 90 11:21:43 PDT
From: [e-mail] (Jim Bowery)
Subject: Re: National Space Society

Craig Ward's attempt to excuse NSS's distribution of a leading
"survey" as a pragmatic way to garner membership is a better
demonstration of the failed character of NSS and it's current
supporters than I could have hoped for.

The claim that NSS's leading survey is simply doing what all
organizations must do in recruiting supporters fails to address
the main concern of the vast majority of us who felt that it
tricked people to give answers which NSS could say support NASA's
current programs, such as Space Station.  How does this help NSS
gain members?

But the worst condemnation of NSS and its supporters is the constant
use of the results of such "surveys" to claim that the "grassroots"
want every greater expenditures for a bankrupt "space program".  When
those responsible for such "grassroots" misrepresentation, such as
Scott Pace, then seek positions within civil service, it only consumates
the sleaze.

NSS and its supporters are attacking the foundation of democracy on
behalf of those in NASA who would force all progress in space to be
dependent on them, using a "survey" barely worthy of a third world
communist government's bureau of propoganda.

When one reflects on the critical stage we are at, not just as a
nation, but as a planet, NSS deserves every bit of the condemnation
it receives, and far more.

If they are lucky, history will simply forget those, such as Craig Ward
and Scott Pace, who, in their craven submission to bureaucracy, helped
cripple the spaceward drive.
---
Typical RESEARCH grant:
$
Typical DEVELOPMENT contract:
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$


-------------------------------
--
William Baxter

ARPA: web@{garnet,brahms,math}.Berkeley.EDU
UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web

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

Date: 13 Apr 90 21:50:59 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 04/13/90 (Forwarded)

-----------------------------------------------------------------
Friday, April 13, 1990               Audio Service: 202/755-1788
-----------------------------------------------------------------

This is NASA Headline News for Friday, April 13.....

The launch target date of the Hubble Space Telescope aboard the
STS-31 Discovery at the Kennedy Space Center is scheduled for
Wednesday, April 25 at 8:29 A.M. EDT.  The new target date
accomodates all critical path activities to include the auxiliary
power unit replacement and recharging the Hubble Space Telescope
batteries.  All will be completed without changing the time-line
for future launch plans.

KSC ground crews are preparing to work in a parallel position to
replace the auxiliary power unit number one.  This will include
depressurizing the APU of hydrazine in preparation for changeout
beginning early Saturday morning.  The new unit has arrived on
schedule for replacement Sunday.

Mission managers have examined the best possible work scenarios
to maximize the most efficient equipment handling options and
minimize the possibilities to contaminate the the Hubble Space
Telescope.  Cautionary steps include a clean air purge through
the payload bay, closing off the platform activity above level
three and keeping the payload bay doors closed during the APU
removal activities.  To date, the detectors that have recently
been removed from the payload bay indicate no concern for
contamination.

Meanwhile, two new detectors will be installed this evening
inside the Discovery payload bay to monitor any contamination
during the turnaround activities.  The Hubble Space Telescope
batteries will be removed on Saturday.  While at the battery lab
at the Vertical Assembly Building, they will be chilled down and
recharged for approximately 130 hours this Sunday.

                       *        *        *
In Other News:

An Arianespace accident inquiry board reports the recent Ariane
44L booster explosion at launch on February 22 is apparently due
to a piece of cloth lodged in a water pipe.

NASA engineers announced a successful test of an advanced Space
Shuttle main engine today.  It was the 19th test firing in the
Marshall Test Bed facility in the West Test Area. The facility is
used to study and evaluate new engine technology.

                           ***********








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

Date: 15 Apr 90 14:38:50 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew![e-mail]  (Brian or James)
Subject: Re: Interstellar travel and the Fermi paradox


 Perhaps the local solution to the Fermi paradox is that, *if* other
technologically inclined species tend to fill their galaxies to the
saturation point in a few hundred millenia, and *if* the conditions
caused by the saturation of the galaxy preclude new technological
species from evolving, then our present existance requires that
the industrialisation of our galaxy has not yet occured. This model
is fairly hard to disprove, so it probably not useful. If other galaxies
do have wide spread civilisations, I wonder if we could detect them
remotely. Perhaps that's the explaination for the 'Great Wall'. The
universe is more or less  identical [in terms of mass/volume], but
the techno types are blocking the visible light with all those darn Dyson
spheres :). I'd expect the big dark areas to be sources of infra-red
radiation, if this were true.
                        JDN

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

End of SPACE Digest V11 #268
*******************