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Name: Danny
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A

Why can you see scars on Jupiter after Shoemaker-Levy 9 Collision with it? Since Jupiter is a gas planet, would it be like a bullet making a mark in smoke?

Dear Danny,

Good question. I think we could see the spots so well because they deposited thick black smoke throughout the upper levels of Jupiter's atmosphere. It was not like a bullet leaving a marking smoke, it was more like bullet leaving a big black mark in very dense gas, gas dense enough to break up the comet itself as it came in. As each fragment hit, it created a "tunnel of fire" in Jupiter's upper atmosphere, and dust came out through that same tunnel of fire, re-landing as particles of a dense soot-like substance, which is what we saw.

David H. Levy

The density of the gas on Jupiter is very large. You could view it as a "fluid" that has a sufficiently high viscosity to retain the trajectory of the comet and planet. A better analogy might be a bullet shot into a chunk of "Jello". We commonly refer to a gas as something with low density and low viscosity. That is the way we usually experience it on planet Earth. The same rules do not apply to the high density fluid that makes up Jupiter's atmosphere.

Vince Calder

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