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Name: nathan
Status: student
Age: 11
Location: N/A
Country: N/A
Date: 1999 - 2000

why doesn't the tail of a comet melt when it orbits the sun?

Because it's already melted. In fact, the comet head is a big snowball mixed with dirt, and what happens when it comes near the Sun is that the Sun starts melting it. Then all the water comes streaming off the comet head, and the Solar wind blows it out beind the comet in a big tail. So you see, the comet tail is already melted. It's like the jet of steam you see coming out of your tea kettle when the water is boiling like mad.


The tail of a comet is not a solid object; it is a cloud of gas. It has already melted, or more likely sublimed (changed directly from a solid to a gas) because of the heat from the sun and the vacuum in space.

Tim Mooney ( (630)252-5417
Beamline Controls & Data Acquisition Group
Advanced Photon Source, Argonne National Lab

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