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Why does it have to be a hydrogen snowball? Because no tail was detected that would have indicated a dirty methane-etc snowball? What about an stony asteroid-
by kristianp 6y ago
Why does it have to be a hydrogen snowball? Because no tail was detected that would have indicated a dirty methane-etc snowball? What about an stony asteroid-like object?
- petascale 6y agoQuoting the article: "While a few other substances (like solid neon) could potentially explain the coma-free acceleration, hydrogen was the best match for the data." It doesn't have to be hydrogen. But to explain acceleration from solar heating it does need outgassing, and the outgassing has to be in a form that we can't detect (no comet tail). Stone won't have much (or any) of that.