Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_6/V13_615.TXT

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Subject: SPACE Digest V13 #615

SPACE Digest                                     Volume 13 : Issue 615

Today's Topics:
           Re: Keck (was Re: Privatization)
    Mars polar sampler (was:  Re: Why the space station?)
       Re: Kelly Act (was: Re: Building Infrastructure)
            Re: Asteroid Hazard Avoidance
            space news from April 8 AW&ST
      Babies in Space (was: Terraforming Mars?  Why not Venus?)
        Re: Terraforming Mars?  Why not Venus?
             Re: Building Infrastructure

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 22 May 91 04:04:25 GMT
From: groucho![e-mail]  (Steve Emmerson)
Subject: Re: Keck (was Re: Privatization)

In <[e-mail]> [e-mail] (Jonathan Leech) writes:

>    I've brought this up a few times before to be roundly ignored, but
>perhaps some discussion will happen this time.    My feeling is that
>space science, particularly planetary science, is grossly overfunded
>in proportion to its science return.  (For those who think not: would
>you be willing to have the $2G NASA science budget transferred to NSF
>and subjected to the same peer review process as other NSF funded
>research?  If not, why not?)

I would (though I suspect my opinion is in the minority).

Didn't the Augustine Report, however, specifically say that *science*
should be deciding factor for the space program?  If so, your suggestion
would appear to be right on the mark.

Would those who have read the report please comment.

Steve Emmerson        [e-mail]        ...!ncar!unidata!steve

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

Date: 22 May 91 02:14:34 GMT
From: eru!hagbard!sunic!mcsun!ukc!edcastle!aiai!aipna!cstr![e-mail]  (Richard Caley)
Subject: Mars polar sampler (was:  Re: Why the space station?)

In article <[e-mail]>, Steve Schaper (ss) writes:

ss> Would it possibly be less costly to send the polar corer probe
ss> with onboard electron microscope, gas chromatograph, etc,

Maybe, but it would be a _real_ pain when you and discovered that what
you really needed there was microsubluction boozalatron which, of
course, is developed 2 years after the probe is launched.

--
[e-mail]            _O_
                     |<

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

Date: 23 May 91 22:02:43 GMT
From: sequent!muncher.sequent.com![e-mail]
Subject: Re: Kelly Act (was: Re: Building Infrastructure)

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:

>Moving mail was NOT a reason
>for the bill.

References please?  The Kelly Act was in fact a project for airplane
mail carrying, _not_ passenger carrying, from a literal reading of the
Act.  It was government mail, not passengers, being paid for.  While some
of the promoters may have been envisioning air passenger carraige,
the mail business was _the_ business of, and the major motivation for,
the Act.

Furthermore, I might point out that long-distance carraige of people,
including government officials, was also a large major market, with
speed also of the essence.  Even if you could demonstrate that the
Kelly Act was promoting passenger rather than air mail, it would still
be an example of a current market being exploited with an existing,
working technology, not the development of speculative technology for
a speculative market.

Finally, it would be useful to know the dollar amount, translated into
current dollars, spent on the Kelly Act versus the revenues.


--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 24 May 91 00:01:59 GMT
From: sequent!muncher.sequent.com![e-mail]
Subject: Re: Asteroid Hazard Avoidance

> AIAA says the asteroid passed through Earth's orbit just 6 min. after
> [Earth] was there, and no one saw it coming."

Somewhat simplified, the problem is this: they are small, dark, and
there are millions of them.  We know the whereabouts of less than
1% of these earth-crossing objects.

Two programs would go a long way towards increasing our knowledge of
the whereabouts of earth-crossing objects:

* An infrared telescope dedicated to the discovery of asteroids and
  comets.  IRAS discovered as many as ten thousand new asteroids and
  comets, but most of these have been lost, because IRAS was designed
  and used primarily for observation of other star systems.  It requires
  three or more photographs separated in time to be able to determine
  the orbits of new asteroids, and IRAS did not take these.  Infrared
  is able to see those dark comets which absorb sunlight and give it off
  as infrared.  An infrared telescope, costing perhaps $100 million,
  (or as little as $30 million for a small version launched on a Pegasus),
  could discover and track thousands of new asteroids and comets, many
  of them earth-crossers.

* A ground-based visual search.  Currently a small group of people,
  but primarily Eleanor Helin, are undertaking this search.  This
  needs to be expanded to include several dozen full-time astronomers
  with several hundred somewhat larger, automated telescopes with photo
  plates and CCD's.  A visual search complements the infrared search
  and enables more detailed analysis of the size and material contents
  of the objects.  The cost of this over 10 years would also be in the
  range of $100 million.

As a cost comparison -- remember the need to compare alternate needs and
solutions -- Hubble cost over $1,000 million; Fred is estimated at
$120,000 million, and the Shuttle now costs in the range of $4,000
million per year.

The infrared telescope and ground-based visual search would also lead
to the discovery of a wide variety of space material resources -- water,
metals, etc. -- with very little energy cost to and from earth orbits,
judging from the statistics of earth-crossing asteroids and the progress
that has already been made during the last decade by the great explorers
Eleanor Helin and Eugene Shoemaker.  One asteroid discovered by Helin,
1982DB, has an energy return cost that would allow 9,000 tons of materials
to be shipped to Earth orbit for every 1 ton that could be shipped from
the lunar surface (reference: _Breaking the Bonds of Earth_, Lewis & Lewis,
1987).  It is likely that thousands of such asteroids exist, with
makeup ranging from refined nickel/iron to carbon/water/clay/polymers
to possibly even dead comets with dust-covered water ice.

Finally, there are several "pure science" mysteries that this search would
help solve:
* The fate of short-period comets (many earth-crossers may in fact be
burnt-out comets)
* The origins of the various types of meteors found on Earth
* The size distribution of Earth-crossing objects and how it relates
to cratering events, including the mass extinctions of life on Earth
* The origins of the solar system itself, since asteroids and comets
represent its most primordial constituents.

In protecting, extending, and learning origins of life, we have
much to gain by learning more about the earth-crossing asteroids.



--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 24 May 91 04:15:12 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from April 8 AW&ST

[Unless I've mislaid it somewhere -- possible -- my copy of the April 1
issue didn't turn up.  I'll do it if and when I find/get it.]

The cover is "Military Space Technology Advances", the picture being an
ultraviolet image of a sounding-rocket exhaust plume as seen from LACE.

Editorial mentioning the 30th anniversary of Gagarin's flight, observing
that the Soviets made a major effort to spruce up Baikonur for the
celebration.

Japan's Space Activities Commission approves initiation of Comets (a 2-ton
research satellite to investigate mobile communications) and Lunar-A (an
ISAS project to launch a lunar orbiter with three penetrators in 1996).

Soviets approve launch of a US teacher to Mir in 1993, in an agreement
between NPO Energia and Aerospace Ambassadors (a project of the Aviation
Space Education Association).  The teacher will fly free of charge, but
sponsors are being sought to fund a set of experiments "to help defray
costs" [it's not clear quite what this means].  [Hmm.  Very hmm.  With
the Shuttle teacher-in-space program being postponed one year per year,
this might well be the first US teacher in space.]

Israel makes second test launch of its Arrow ATBM from a ship in the
Mediterranean.  Photograph, not very informative.  The next flight will
be an attempt to intercept another Arrow, later this year.

Major management shakeup at Eosat.  No reasons given.

The big space story in this issue is definitely the leak of Timberwind.
AW&ST says it has independent confirmation based on documents, although
SDIO declines all comment.  Timberwind has cost $40M to date [which makes
it a small study program, by the way, not a major development effort],
and would probably cost $7-8G through flight test.

Timberwind is a fluidized-bed reactor, with small pellets of nuclear fuel
supported by the gas stream.  Exhaust velocity will be much higher than
an oxyhydrogen engine, despite similar temperatures, because of the much
lower molecular weight of the hydrogen exhaust.  [Exhaust velocity scales
inversely as square root of molecular weight, giving a factor of 2-3.]
At least one fluidized-bed reactor was tested briefly in the mid-1980s,
although it was not entirely successful.  The engine would have a thrust
of 45-75klbs initially, with possible growth to 250klbs.  AW&ST's drawing
indicates use of a telescoping exhaust nozzle to reduce length, *presumably*
extended before ignition.

Two design concepts using the Timberwind engine have been sketched.  One
is an Atlas-Centaur derivative, with the Centaur replaced by a huge stage
(fatter than the Atlas and twice as long!!) using a single Timberwind.
The Atlas sustainer phase would be eliminated, with all three Atlas engines
cutting out simultaneously before staging.  This configuration could lift
about 27klbs to low orbit.  The other concept is an "advanced Titan" scheme
which sort of jacks up Titan's SRBs and slides an entirely new rocket in
between, using three Timberwinds igniting at SRB burnout.  Payload to low
orbit would be 140klbs.  [Hmm, I wonder if they've thought about the problems
of nuclear clustering?  One has to beware of interactions between reactors,
since they are unshielded and right beside each other.]

SDIO proposes initial engine testing at the Nevada Test Site, followed by
a suborbital test over Antarctica.  (Some small chance of an accident
affecting New Zealand is noted.)

NASA is interested in Timberwind but is wary of public outcry and suspects
that commitment to a specific advanced reactor design is premature.  [They
would prefer to spend half a decade studying it first, as usual.]  They are
also skeptical about possible development problems, especially weight growth
that could give it little advantage over a more conventional Nerva-type
engine, and doubt that political approval could be had for igniting nuclear
engines before reaching orbit.

Lockheed gets the "technical partner" contract from Motorola for Iridium.
The funding consortium, to which M+L would be prime contractors, remains
unformed, and spectrum allocation for Iridium will be in doubt at least
until the WARC meeting next Feb.

First operational Almaz radarsat launched from Baikonur March 31.  Images
will be marketed through Space Commerce Corp.  Some Soviet agencies think
this is a mistake, saying that the Soviet Union needs to develop its own
marketing expertise.

Soviet general says USSR "considering retaliation", politically or with
military development, if SDI development continues, claiming that SDIO's
attempts to re-cast its plans in terms of tactical defence and accident
prevention are a smokescreen for full deployment.  He suggests one likely
countermeasure:  mass production of warheads and missiles to swamp any
specific defensive system.

The government of Kazakhstan is trying to charge the central Soviet
government rent for the land occupied by Baikonur.

Boom.  Upgraded Titan IV SRB explodes during first test at Edwards.  [AW&ST's
pictures, however, are disappointing.  The one on the front page of Space
News was much better.  Must have been quite some fireworks display.]  No
injuries, but the test stand is badly damaged, and that plus the failure
will probably delay introduction of the new (Hercules) SRB.  The current
(United Technologies) SRBs are available in sufficient number that Titan
launch schedules should not be affected.  Cause of the explosion is not
yet known, although some problem with the fuel is considered more likely
than a flaw in the new composite casing.  The new SRB is a major redesign,
using longer segments (for the sake of fewer joints) in addition to the
new casings and other improvements.

Major story on military-space implications of Desert Storm.  Smaller and
lighter satellites dedicated to tactical applications are definitely in.
Comsat capacity was grossly inadequate.  An experimental Darpa lightsat
saw operational use for digital data relay.  Tactical missile warning is
another big growth area.  Details of various R&D projects, including the
Truax/NRL project for a sea-launched recoverable booster.

Weather-satellite night image of the Gulf, showing oilfield fires and
complete lack of electrical power in Baghdad and surrounding areas.

European interest in independent spysat capability, for early warning
and treaty verification, sharply up in the wake of the Gulf War.  One
specific proposal is to follow the two Helios spysats currently planned
with a third carrying an imaging radar.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 23 May 91 19:17:10 GMT
From: mtxinu!sybase!alf![e-mail]  (brook mantia)
Subject: Babies in Space (was: Terraforming Mars?  Why not Venus?)

In article <[e-mail]> [e-mail] (Lloyd E Vancil) writes:

>Yes reduced gravity should cause problems for pregnancies and growing
>children
>

Why?  Esp. for pregnancies.  I'd imagine reduced gravity might make pregnancy
easier.  Just wondering...

Cheers,
Brook Mantia

PS:  If anyone knows of any good reference material regarding this subject
I'd be very appreciative. Thanks.

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

Date: 22 May 91 21:55:06 GMT
From: agate!spool.mu.edu!sdd.hp.com!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!maverick.ksu.ksu.edu!uafhp![e-mail]  (Brian McCormick)
Subject: Re: Terraforming Mars?  Why not Venus?

In article <[e-mail]>, [e-mail] (Frank Crary) writes:

> >   What would [bacteria] chomp [sulfur] into?
> > ...there's still going to be sulfur somewhere,
> >and you have to do SOMETHING with it. I assume that most heavy compounds
> >that might settle to the surface would break down eventually in the
> >heat, pressure and miscellaneous chemicals.
> >
> While I am not a geologist, I seem to remember that sulfur is not an uncommon
> component of rocks here on Earth. Venus is assumed to have about the same
> ammount of sulfur as the Earth, (having formed from roughly the same
> material and being roughly the same size.) As I understand it, the problem
> on Venus is that most of the sulfur is in the form of gasses.

I agree.  The real issue is not to get rid of the sulfur, it is to
cool off the planet.  If the planet is cooled off, the sulfuric
acid will precipitate and fall to the surface where it will no doubt
react with minerals present there.  IMHO, the same is true of the
carbon dioxide in the atmosphere of Venus.  The Earth may well have
just as much carbon dioxide as Venus.  Where is it?  Carbonate rocks.
Cool off Venus, add water, wait a few thousand years, and Venus's
carbon dioxide will probably end up in the same place.

(Not that I think terraforming Venus is in any way a practical
solution to any existing problem...  Contemplating terraforming
is an interesting "what if?" exercise though.)

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

Date: 22 May 91 21:00:34 GMT
From: agate!spool.mu.edu!sdd.hp.com!cs.utexas.edu!ptolemy![e-mail]  (Richard S. Brice)
Subject: Re: Building Infrastructure

In article <[e-mail]>, [e-mail] writes:
>
> When was the last time somebody did a marketing survey and revenue/cost
> statement for a space station?

Or a Jupiter probe, Venus mapper ...?

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

End of SPACE Digest V13 #615
*******************