Only here for the atmosphere?
With NASA’s New Horizons probe to Pluto about to take off (with any luck) I can’t help but think that it’s a few years too late. Assuming it can be launched by early February, it will swing by Jupiter and arrive at the ninth ‘planet’ in nine years time, which is pretty fast. However, the concept of a Pluto mission has been seriously discussed since the end of the Voyager grand tour and it’s always been pitched as a race against time – Pluto’s tenuous atmosphere is expected to freeze onto the surface as the planet moves away from the Sun (making Pluto effectively a comet, albeit in a low-eccentricity orbit). The last perihelion was in 1989, so more than twenty years before the probe’s arrival. With four of the six instruments which are going to study the “planet” looking at the atmosphere, it’s going to be pretty dull if the atmosphere is sitting on the surface. Recent results show that Pluto’s largest satellite, Charon, has no atmosphere which may suggest the freeze-out has already occurred.
I hope I’m wrong, and of course there is a proposed extended mission to several other large outer-solar system bodies. But it does seem like a shame that it’s been left so late.
