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From: eugene@ames.UUCP (Eugene Miya)
Newsgroups: net.space
Subject: Re: Money to burn
Message-ID: <1010@ames.UUCP>
Date: Wed, 29-May-85 21:08:20 EDT
Article-I.D.: ames.1010
Posted: Wed May 29 21:08:20 1985
Date-Received: Fri, 31-May-85 05:38:49 EDT
References: <1925@mordor.UUCP> <350@aurora.UUCP>
Organization: NASA-Ames Research Center, Mtn. View, CA
Lines: 67

> > Assume for a moment that we were not in bugetary hard times and could
> > afford an attack of conspicuous consumption. Could a reasonable
> > interstellar
> > one-way unmanned probe mission be designed which would give some legitimate

Unmanned missions with the exception of Voyager have not caught the
imaginations of men.  Voyager did so only because of the timing of events such
as Cosmos, KCET's telecast Voyager coverage, and the diversity of the photos
returned by Voyager.  You could probably assemble a set of questions like "what
planets have we landed" which would measure the impact of these missions and
find lots of confusion.  Another problem with earlier missions was that many
photos returned like Mariner Mercury, early Mars pictures, and so on had
cratered surfaces looking like the moon.  This is hard to excite the brain.
"If you've seen one moon-like planet, you've seen them all?"

> > 	2. Must be ready to launch within 5 years.
> 
> Not a prayer.  Almost nothing gets launched within 5 years of conception, 
> even very
> straightforward build-another-one-just-like-the-last one spacecraft.  The
> only exception to this, I believe, are some communication satellites.

I personally think this is a sad bit of NASA.  It would be nice to be able
to respond to short lived phenomena such as cometary encounters. (hint, hint)

> > 	3. Assume a target star 20 light years away.
> > 
> > 	4. Intial data must be received from target star system within 100
> > years. An interesting question is what collection strategy to use. You
> > could
> > adopt a cometary orbit or try to look for planetary body etc. Minimum
> > requirement is a fly-through at less then .05C mean. Remember that your
> > communications lines have a 40 year turnaround. May be allowed a 10%
> > extension on time limit given a high grade justification.
> > 
> > 	5. Maximum cost will be 1 billion in current dollars. It may be
> > competing in Congress with a submarine base in Arizona so the cheaper
> > the better.
> 
> No chance whatsoever.  The shuttle launches will cost you $140 million alone,
> and most of your cost will be engineering salaries for design and
> construction at $60 - 100 an hour.

Again, I think a sad commentary.  Space flight is expensive in terms of
engineering resources.  It might be useful if we had a class of expendable
special purpose boosters.

> > 	6. Worship the KISS principle. This thing has to go a long way on
> > it own.
> 
> Don't forget a lot of redundancy.

Important.  You cannot stepwise refine hardware once it's in flight.

I thought this question was interesting from the stand point of materials
science and autonomous vehicles.  We really don't know how well our earthly
materials will withstand the rigors of deep space.  We have learned a lot
from the last two pairs of deep space missions.  How would you handle a
craft hit by an astroid before leaving the solar system?  Would you give up
or have the robot try and repair itself.  Sounds expensive. Lots of
interesting, fun questions (sorry, can't answer some for $1G).  Wish I had
more time.

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene
  @ames-vmsb.ARPA:emiya@jup.DECNET