🚀 go-pugleaf

In article <5849@pdn.nm.paradyne.com> alan@rnms1.UUCP (0000-Alan Lovejoy) writes:

| Then we also need either very advanced AI, very advanced biotechnology,
| or artificial gravity: It appears that low gravity fields shut down the 
| human immune system in a way similar to the AIDS virus.  Humans will NOT 
| be spending any appreciable percentage of their lives in space until we 
| can fix our immune systems so that they tolerate low gravity,  or until
| we can provide gravity artificially.  As things stand, a career as an
| asteroid miner would not last long...

  What are the parameters on this? I know the Russians had people in
orbit for almost a year (didn't they?) and didn't seem to have problems.
They were visited by other cosmonauts during the time so they weren't in
a sterile atmosphere.

  I want to make a hypothesis: we won't go the the belt in any short
time unless we actually get room temperature fusion working. Given that
a fusion powered ship seems a certainty. Can I assume a hydrogen ram
jet? I will guess that the distance is 61 million miles. If you assume
that the constant acceleration is 1 fps^2 I think it takes about 13.1
days for the trip. At 1/10G it would take 7.3 days.

  If I didn't drop a deciaml place we are taking about a short journey
here... even assuming 0.1 fps^2 I get 41.5 days. This sounds too good to
be true, and if you extrapolate to 4.5 lightyears it still looks like
space flight is possible.
________________________________________________________________

Since this sounds too good to be true, here's what I did:

 1) S = at^2 / 2
 2) t = sqrt(2S / a)
	if we assume that we accellerate half way and
	decellerate half way
 3) t = 2 * sqrt(S / a)
	S = 65e6 * 5280 (feet)
	  a	sec	days
	====================
	  .1	3589317  41.5
	 0.1	1135041  13.1
	 3.2	 634507   7.3

If I didn't make a silly mistake in the equasions, which seems likely
given the results, or if I have overestimated the power of a fusion
powered hydrogen ram jet, please let me know.

Also if someone has info on such a jet as far as implementation or power
it would help quantify the discussion.
-- 
	bill davidsen		(wedu@crd.GE.COM)
  {uunet | philabs}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me