Space Forum / Space Flight / January 2004

Is there any known or guessed quantity of He3 on asteroids or dead
comets? If an object has been orbitting for 4+ billion years, it
should have collected some from the solar wind. It seems that He3
would be easier to obtain from something like Eros than the Moon, if

Suppose there was a "hypervelocity squirt gun" that could inject fuel
into a scramjet at the same speed that the air was rushing by. This
would mean no supersonic combustion. Of course, the "squirt gun" would
have to be able to shoot fuel at Mach 10+. If such a thing existed,

What's the situation with Spirit (Mars rover) now please?
Is it back to full functionality or is it stationary and just sending
pictures back?
E.F.

It seems that for rockets of multiple stages with only one fuel combination,
there is an interesting engineering decision.
Consider a two stage rocket where both stages burn the same fuel
combination.

Research baloons have flown at 51km above sea level, and yet the
sputnik 1 flew at 31km. 20 km below where the highest baloon can fly
would yield enough resistance not to allow that, so I have this
question: How high is the lowest possible orbit and how high is the

If something physical or meta-physical happened whereby the Moon's
orbit was suddenly changed to an apogy of just within Earth's
gravitational pull (sorry, don't know the distance) and a perogy of
150,000 to 175,000 miles:

I've read in few articles dealing with the priorities change
in NASA that HST will be let to naturally die as a result of Shuttle
service missions cancellation. Why is it considered such an absolute
requirement to have a manned service mission? If memory serves, a Shuttle

I have recently found out that a hamster was levitated by applying a
strong magnetic field of 16 Teslas using a superconducting
electromagnet.
This is significant to me because you could use the technology to

It seems intuitive that, if the technology for SSTO is not quite here yet, it
should be possible to do the job by building an RLV which is almost capable of
SSTO by itself and then add strap-on boosters, solid or liquid.  Yet I've read
that, in RLV design studies, this does not work ...

Would it be possible to build one enormous single stage solid launcher and
offset the cost of the quantities involved by the saving on the
technological costs of multi-stage elements in a conventional launcher?
What I mean is, an oversized "Minuteman" type with a guidance ...

I note from the BBC News site
http://news.bbc.co.uk/1/hi/magazine/3429857.stm today that "moondust
is composed of 40 per cent oxygen".  Also that ""One of the most
restricting facets of lunar exploration is the dust and its adherence

I keep reading that there designs being made for rovers being sent to
Europa.  Why do you need to have an ice melting lander?  Couldn't you impact
a large object into Europa and hope it breaks through the ice layer?
Another option could be detonating hydrogen bombs on one specific ...

I have a question that may have an obvious answer but I have lost too
many brain cells for it to be obvious to me.
isp is given as the thrust produced/quantity of fuel/sec used.
Pounds/(Pounds/sec) gives units of seconds for ISP.  Do the same in

Anyone know the delta-V to move Hubble to 51.6 degrees (while keeping
it near 600 km altitude).  What would be the amount of required
propellant, assuming a 300 sec ISP engine?

Would it make any sense to design a surf launched tourist vehicle which is
spun up while floating in the water? This could then be a totally passive
guidance 'system'. Just point it straight up, spin, then launch. Not a
transistor