Message-ID: <cZQrV2y00VcJE9UU5Z@andrew.cmu.edu>
Reply-To: space+@Andrew.CMU.EDU
From: space-request+@Andrew.CMU.EDU
To: space+@Andrew.CMU.EDU
Date: Wed, 29 Nov 89 01:33:39 -0500 (EST)
Subject: SPACE Digest V10 #286

SPACE Digest                                     Volume 10 : Issue 286

Today's Topics:
     Re: Kvant 2 expansion preceeding to Mir though with problems
   Re: Problems with D module launched to USSR's Mir space station
		   Re: Why NASA wants to go to Mars
	       Re: Looking Down [was: Re: HST resoluti
		   Re: Why NASA wants to go to Mars
----------------------------------------------------------------------

Date: 29 Nov 89 04:54:13 GMT
From: shelby!csli!jkl@decwrl.dec.com  (John Kallen)
Subject: Re: Kvant 2 expansion preceeding to Mir though with problems

I've been reading the news about mir on sci.space with great interest.
I often wonder exactly how is Mir configured at the moment? I.e. does
anybody have schematics or diagrams of what the station looks like
(with dimensions &c)?

TNX
_______________________________________________________________________________
 | |   |   |    |\ | |   /|\ | John K{llen         "God hates me. *That's* 
 | |\ \|/ \|  * |/ | |/|  |  | PoBox 11215          what it is." "Hate Him 
 | |\ /|\  |\ * |\ |   |  |  | Stanford CA 94309    back; it works for me."
_|_|___|___|____|_\|___|__|__|_jkl@csli.stanford.edu___________________________

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

Date: Tue, 28 Nov 89 11:40:00 PST
From: Peter Scott <pjs@aristotle.Jpl.Nasa.Gov>
Subject: Re: Problems with D module launched to USSR's Mir space station

bfmny0!tneff@uunet.uu.net  (Tom Neff) writes: 

>If you didn't need to man rate everything it wouldn't
>be so big, fragile and complex in the first place.  Not that a research
>station isn't a good thing for someone to have up there, but leave us
>not pat ourselves on the back overmuch simply for being able to patch up
>problems our presence itself created.

Seems that you could save quite a bit on building stuff if you knew that
man-repair was possible if something went wrong.  You wouldn't have to
include hardware for every conceivable contingency, you wouldn't have to
construct elaborate robotical devices for each mission to repair itself,
you wouldn't have to build multiply-redundant circuits for repairing
multiply-redundant circuits... you could take a risk or two instead.

Peter Scott (pjs@grouch.jpl.nasa.gov)

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

Date: 29 Nov 89 01:37:42 GMT
From: rochester!dietz@louie.udel.edu  (Paul Dietz)
Subject: Re: Why NASA wants to go to Mars

I am amazed that people are supporting a $400 B project that will
send four people briefly to Mars.  Even if you ignore science,
what could possibly be the justification for this?  $400 B is
an enormous amount of money (for example, it is over 1000 times
the annual US fusion research budget).

I suppose the problem is that people are once again confusing their
fantasies (glorious visions of man conquering the cosmos) with what
NASA is actually proposing (Apollo-like dead end projects that
do little but waste money and boost the ego slightly).

	Paul F. Dietz
	dietz@cs.rochester.edu

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

Date: 28 Nov 89 19:22:42 GMT
From: psuvm!mrw104@psuvax1.cs.psu.edu
Subject: Re: Looking Down [was: Re: HST resoluti

In article <110700010@uxa.cso.uiuc.edu>, sfn20715@uxa.cso.uiuc.edu says:
>
>Just a second here.  I agree that the HST would have a resolution on
>earth of ~6 inches, but dont DoD Spysats have a resolution of about
>2 inches?  Why dont we just tell the DoD to point one of em at whatever
>astronomers want to look at?  I'll admit this would probably be like
>squeezing blood from a stone but even if we used some of the Fed's junk
>in space (resoloution of 8 inches???) we could get good data.

That would be  great idea, except that the DoD satellites probably don't have
that kind of resolution, but if they did, they would have visual light and
infra-red cameras. Visual light is more or less a back-seat kind of field
right now- it's all UV or x-ray or radio, with some IR. Even the IR cameras
might not help much, becasue their peak sensitivity range would be great for
seeing car or tank exhaust, which might be a very boring region of the astro-
nomical sky.
Assuming for the moment that the DoD satellites had the equipment to study deep
sky objects, the problems involved in pointing the satellite in another
direction are enourmous. The camera points 'down' relative to the Earth, which
is the same direction that the communications and navigational gear points. If
you flip the satellite over on its back, it can 'see' in the right direction
but it won't know where to aim, or where to return the data to, or even how
to rotate back to Earth. Once its navigational gear no longer points to the
Earth, the satellite is 'lost' and only a lucky trial and error attempt will
get it pointing in the right direction again. Remember, when the satellite is
on its back, it can recieve no instructions from the ground.
Even if all these problems are overcome, the DoD satellites just aren't
designed for astronomical work. I don't think they have the pointing accuracy
necessary for long-durational photography.

****************************************************************************
Mike Williams
mrw104@psuvm.bitnet

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

Date: 29 Nov 89 00:58:44 GMT
From: uhccux!goldader@ames.arc.nasa.gov  (Jeff Goldader)
Subject: Re: Why NASA wants to go to Mars

In article <5096@cbnewsc.ATT.COM> dhp@cbnewsc.ATT.COM (douglas.h.price,45261,ih,6x203,312 979 3664) writes:
>$400 billion applies if we continue to use 'standard' chemical rocket
>technology to get to Mars.  If I invoke the nuclear propulsion 
>technologies (eeek! the dreaded 'N' word!)  the cost drops quickly to
>about $150 billion with our current understanding of the life support
>issues and the launch of all mass for the mission from earth.  This
>is obviously a mite easier to digest.  As as been noted in the NIMF
>proposal from Martin Marietta, in some mission scenarios you can do
>the entire mission with a single Shuttle-C launch!  That's cheap!  But
>due to the politics of the situation (see the RTG battle) there is no
>way we are going to do it in the current technophobic climate.
>
And at that price, even *I* would say, "GO!"  Even more useful than the 
Mars aspect would be the development of fast propulsion systems, which
would really enable exploration/exploitation in a speedy, efficient,
hopefully cheaper manner (heck, I'd love to see an asteroid being towed 
into orbit- the whole program would pay for itself easily).

I just feel the current Mars mission is a run there, run back sort of
thing, which will cause more problems than good.  And it's still too
expensive.

And yup, the "N" word is strictly forbidden.  Unfortunately.

Jeff Goldader                        University of Hawaii
goldader@uhccux.uhcc.hawaii.edu      Institute for Astronomy

"So, Lonestar, now you see that Evil will always win- because Good is stupid."
-The Dark Lord Dark Helmet, _SPACEBALLS_ 

Disclaimer: The University of Hawaii and the Institute for Astronomy neither 
support nor are in *any way* responsible for these opinions.

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

End of SPACE Digest V10 #286
*******************