Originally Posted by Sol88
Little hint for the hard of thinking - the high temperature material must have originated in the inner solar system. From there, it is blown outwards by the activity of the young Sun. As I believe we have observed (not the material, but the activity that would send it into the far reaches). And the instruments certainly don't have error bars of > 300 K! That would be a bit useless, and not worth putting on the spacecraft! It was ~ 5 K at Tempel 1 and Hartley 2.
The temperature, thermal inertia, roughness and color of the nuclei of Comets 103P/Hartley 2 and 9P/Tempel 1
Groussin, O. et al. (2013)