🚀 go-pugleaf

In article <1989Jan20.193344.9479@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:

>>His comments about the scientific track record of manned vs.
>>unmanned flights are cogent...
>
>Interesting, yes.  I'm not sure I would say "cogent" without first talking
>to people like the solar astrophysics types (remember the Skylab Solar
>Telescope and the Solar Max repair?), not to mention the lunar geologists.

Let's talk about repair of spacecraft.  At current launch costs, it's
a joke.  You'll notice Solar Max will not be reboosted.  Let's look at
another example -- HST.  With the shuttle it would have been cheaper
to build and launch multiple HSTs than to retrieve one from orbit for
refurbishment.  For on-orbit servicing: three or four repair missions
equals the cost of building and launching a new HST.  Since putting
HST into low orbit where the shuttle can reach it reduces the fraction
of time it can be used by a factor of three, is it any wonder the
astronomers would much rather have free flying instruments that are
not dependent on the shuttle?

As for lunar geologists: they will tell you that Apollo isn't around
any more.  It was far too expensive.  An unmanned program might have
taken longer, but it would have been a lot cheaper, would have let us
see more of the lunar surface, and might still be ongoing.

>If one's priorities are short-term gain (be it financial or scientific),
>then of course one gets upset about long-term investments.  Some would
>question those priorities, however.

I believe scientific investigation is a long term investment.  This is
orthogonal to the issue of the effectiveness of a particular
investment.  We can do a lot more science per dollar, in general, with
unmanned spacecraft than with manned spacecraft, at current launch
costs.  Curious how NASA has decided that those areas of science that
seemingly require people in space are the most important.

The long term viewpoint does not require the immediate gratification of
seeing people in orbit in the present.

>>It is disingenious to pretend that recent NASA emphasis on manned
>>spaceflight, the shuttle program in particular, has not had a major
>>negative impact on planetary and space science.
>
>It is also dishonest, not to mention foolish, to pretend that cutting
>back manned spaceflight would boost planetary science.

If experience is a guide, not cutting back manned spaceflight (the station)
*will* further damage unmanned spaceflight and, by delaying investment
in truly useful technology, like better boosters, it will damage manned
spaceflight in the long run.

>>What about unmanned asteroid exploration?  A lunar polar orbiter?
>>Probes to Phobos?  Our knowledge of ET resources is still rudimentary.
>
>Agreed, but please observe the word "need".  These things would indeed
>be useful.  (I note that most of them don't seem to be high priority for
>the space-science bunch.)  But they are in no sense prerequisites.

Something is needed then.  I notice we aren't building space colonies
now, and it isn't because of some epidemic of timidity.

	Paul F. Dietz
	dietz@cs.rochester.edu