On 2 Feb 2008, jdnicoll@[EMAIL PROTECTED]
(James Nicoll) wrote:
> In reality, if someone dumped an FTL drive like that in our
>laps, one that offers no quick solution to getting around in stellar
>systems, where the jump point isn't conveniently located, how long do
>you think it would take before someone got around to sending a probe
>out to the jump point?
I'm replying here because I've got some new points, and the rest of
the discussion has diverged into heated animosity.
1. ISTM that space probes take years to develop because of the
necessity they be low-mass: there's little margin for structural
redundancy, so most everything has to be custom-made. With a bigger
mass budget, you could dispense with a lot of the optimization and
testing.
2. Can you solve this problem by throwing more money at it? Maybe.
The SpaceX (www.spacex.com) Falcon 9 is rated for 5,000 kg payload to
LEO when launched from Kwajalein Atoll (9°N), at a cost of $55M. The
Falcon 9 Heavy can do 11,500 kg, at $90M.
Of course, the Falcon 9 hasn't been flight-tested yet (it won't before
2008Q4), and neither of the Falcon 1's reached space, but its rapid
development (since ~2005) bodes well. For this hypothetical scenario,
anyway.
For comparison, the Cassini-Huygens Saturn probe massed 5,820 kg, of
which 3,100 kg was propellant.
3. And why do we have to fit the entire probe and its upper rocket
stage in a single launch vehicle? If it's really important to verify
jump point, why not assemble the craft in orbit, from several
launches? The development of automated rendezvous systems in the ESA
_Jules Verne_ craft (to resupply the ISS), and fuel transfer with the
USAF's recent automated orbital resupply test, demonstrate that
capability.
4. As for practical orbits to the vicinity of Saturn -- I'm sure
someone with an orbital simulation program and experience using it
could enumerate the direct-flight options in a few minutes. Something
like STK/Astrogator, from Analytical Graphics:
<http://www.agi.com/solutions/specializedAreas/spaceOps/>
Looking for suitable gravity-assists probably takes exponentially
longer.
(I'm sure there must be "toy" orbit-planning software out there,
something for a first-cut approximation, but my Google-fu has proved
unequal to the task.)
Mission planning gets easier (so I presume) if you have enough delta-v
to overcome the confounding effects of third bodies on your transfer
orbit.
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