[Outbackmanyep]

Originally Posted by Jarvamundo

Questions:
* What do you suggest the crust is made from? if no surface ice detected?
* Given the size of the explosion (blinded the camera to saturation levels), would the vaporization blow out this crust? It would have to yeah... if thats what you are claiming we see?

A couple of things, they did detect surface ice on 9P/ Tempel 1!
http://www.nasa.gov/mission_pages/de...water_ice.html
http://www.ncbi.nlm.nih.gov/pubmed/16456037


The sublimation of ices produces a porous dust mantle, this insulates the ices beneath the surface and perhaps regulates the rate of sublimation. The sublimation is believed to occur a few cm below the surface and the porous surface allows gases to permeate and escape. Heat flow through the surface provides the mechanism for this to happen. This is compatible with surface temps around 320K and for sublimating ices at 215K.
It has been observed that this process is not unform over the entire surface.
Infrared observations by Vega 1 and Deep Space 1 show that the surface temps of Halley and Borrelly were 312K and between 300 and 345K respectively.
Mind you water ice only really takes off for most comets at 3AU from the Sun, at further distances other ices begin to sublime, CO2 at 10AU, CH2O at 18AU etc.