QUOTE (BruceMoomaw @ Jan 23 2006, 08:18 PM)
There are actually three reasons for getting NH to Pluto as fast as possible, despite the higher flyby speed.
First is indeed the risk that the atmosphere may be about to freeze out,
Second is the fact that, as Pluto moves slowly away from its equinox more and more of its south polar region is being shrouded in permanent shadow
Third, of course, is that the longer it takes to get to Pluto, the higher the operating costs, and the higher the risk that it will fail before getting there. ..
I would like to throw some cold Hydration on this question and Nix it entirely. (Just can't reisit those awful, awful moon name puns.)
Bruce , and disownedsky, are precisely correct, as is the issue of the limit on science being the SSR capacities. There are even more risks and costs to delays. Look at Dawn and SOFIA, which nearly got cancelled for a few tens of millions of dollars, and are still fighting for their lives. As Alan Stern and others have said, New Horizons is in its native element, deep space. Where, I might add, the odds of collision with a rock are way, way less than the odds of colliding with politics here on Earth.
IIIRC, the boost at Jupiter is ~4 km/sec. Arrival speed is >11 km/sec. However, that does not mean that a flight without a Jupiter flyby would arrive at 7 km/sec. The difference would be less than 4 km/sec, because the trajectories would cross at sharger angles. So the increased time close to Pluto would be, as suggested, not significant.
In addition, Alan says that New Horizon's "dirty little secret" is that it will return more science data from Jupiter, due to the "short" range of only ~5 AU. Pluse NH flies down Jupiter's magnetotail to 1000 Rj, which will data not collected at any planet including Earth. And the Jupiter encounter is great practice, a good chance to wring out an encounter sequence.
How could it be any better than with the Jupiter flyby? (I am sure someone will have a suggestion.)