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View Full Version : Interstellar comets, interstellar asteroids



Tom Mazanec
2018-May-24, 06:10 PM
We have been able to notice interstellar comets for several centuries, and have seen none. We've seen comets BECOME interstellar, usually because of Jupiter, but not coming in.
We have been able to notice interstellar asteroids for much less time, maybe a decade, and saw one.
Are interstellar asteroids more common than interstellar comets?

Swift
2018-May-24, 06:18 PM
We have been able to notice interstellar comets for several centuries, and have seen none.
I'm not sure that is true.

I think you are assuming several things, that we would see the object, we would plot a trajectory that would demonstrate it came from out of the solar system, and we would see some characteristic that it was a comet (I'm guessing, most particularly, the formation of a tail).

But would an interstellar comet form a tail? Would it still have volatiles after a very long interstellar journey? Would it get close enough to the sun on such a trajectory that it would form a noticeable tail? I'm not sure of either of those things.

I doubt at this point we have enough data to answer your question.

Lastly, I am under the impression that the difference between comets and asteroids is not a clear cut as it was once considered (asteroids can have a lot of volatiles and comets can have a lot of rock).