Posted on 02/09/2014 12:19:45 PM PST by SunkenCiv
Explanation: Where are the craters on asteroid Itokawa? Missing -- unexpectedly. The Japanese robot probe Hayabusa approached the Earth-crossing asteroid in 2005 and returned pictures showing a surface unlike any other Solar System body yet photographed -- a surface possibly devoid of craters. The leading hypothesis for the lack of common circular indentations is that asteroid Itokawa is a rubble pile -- a bunch of rocks and ice chunks only loosely held together by a small amount of gravity. If so, craters might not form so easily -- or be filled in whenever the asteroid gets jiggled by a passing planet or struck by a massive meteor. Recent Earth-based observations of asteroid Itokawa have shown that one part of the interior even has a higher average interior density than the other part, another unexpected discovery. The Hayabusa mission returned soil samples from Itokawa which are also giving clues the ancient history of the unusual asteroid and our entire Solar System.
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Chive got a feeling you’re right.
Phobos.
Well I had a 50/50 chance.
If you passed that on a hillside on earth, you’d think, breccia and pass it by.
“Extinct comet” implies that all the ice has been sublimated. Some comets break up due to outgassing, and I assume some just become extinct and turn into small asteroids. Maybe some break up and then reform, leaving no ancient craters. It’s just interesting, whether it be wrong or right.
I couldn’t rememember, and started to look for Deimos topics. :’)
LOL He looks a bit like a potato.
:’) The surface of most asteroids probably look a lot like Itokawa — small bits of debris pulled in by the slight gravity. Due to relative lack of competition, asteroids have a large sphere of influence.
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