Re: Rosetta is cool?
The problem for philae being in the sun is that it has nowhere to dump the heat. On the lunar missions they could deploy radiator panels on the shaded side or underside that were not exposed to sunlight (and where thus in the cold) and they could deflect a lot of heat to space. On top of that lunar rigolith is a VERY reflective material and thus stays relatively cool. Philae is only a tiny little probe with a very small shadow so nowhere to dump a lot of heat. It's sitting on a black/gray lump that is catching heat from the sun very well. Philae WAS designed to sit in the sun and roast all day, but at some point there is only so much you can do to stave off heat-stroke.