Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site mmintl.UUCP
Path: utzoo!linus!philabs!pwa-b!mmintl!franka
From: franka@mmintl.UUCP (Frank Adams)
Newsgroups: net.space
Subject: Re: Fuels for rocket propulsion
Message-ID: <656@mmintl.UUCP>
Date: Fri, 13-Sep-85 21:40:43 EDT
Article-I.D.: mmintl.656
Posted: Fri Sep 13 21:40:43 1985
Date-Received: Mon, 16-Sep-85 21:09:54 EDT
References: <384@decwrl.UUCP>
Reply-To: franka@mmintl.UUCP (Frank Adams)
Organization: Multimate International, E. Hartford, CT
Lines: 32
Summary: Interstellar travel


[Not food]

While not disputing any of the specific conclusions in the original article
(concerning spaceship propulsion systems), I think it is overly pessimistic
about the possibility of interstellar flight.  While none of the proposed
systems is sure to work, I think collectively they produce a near certainty
for this development.

The anti-matter drive is probably the most likely to be possible.  While
we don't now have the technology to produce anti-matter at a reasonable
price, it seems likely to me that this will be developed, in one way or
another.  I would rate this technology better than a 50/50 chance.

The economics for ramscoops look much better if you assume there are areas
of higher density than average, where you can "refuel".  As a worst case,
you can fly by other stars, so that the typical distance between stars is
the limiting case.  On the other hand, there may well be sub-stellar bodies
scattered around the galaxy, which would presumably have large atmospheres.

Light sails using ground-based lasers are another good prospect.  You have
to set up an installation at the other end if you want to get back, of
course.

Finally, there may be possibilities which haven't been thought of yet,
perhaps because the basic science required isn't known yet.

In short, I would conclude that we don't yet know how to build an
effective interstellar spaceship, but that being able to do so is only a
matter of time.

Frank Adams                           ihpn4!philabs!pwa-b!mmintl!franka
Multimate International    52 Oakland Ave North    E. Hartford, CT 06108