Title of one os some articles in the recent newsletter from Thunderbolts Project is as follows: Comets May Not Be What We Thought ! Rosetta mission seems to confirm this thesis. Here is the link to the YT films on this subject:
https://www.youtube.com/watch?v=-UliVkgc5s4 (Comets May Not Be What We Thought)
https://www.youtube.com/watch?v=eqxF5u (Oops! No Water on Comet 67P?)
https://www.youtube.com/watch?v=9QMkjPeeVYU#t=122 (Rubble on 67P Defies Current Comet Theory)
There are even no bluish patches of ice! Only rocks, from rubbles, gravels to sand or other dust! Prediction and theory of EU comets seems to be correct, conventional comet's nucleus explanations probably refuted!