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Old 03-September-2003, 12:04 PM
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kucharek kucharek is offline
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Join Date: Feb 2002
Location: Karlsruhe, Germany, Old Europe
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Quote:
Originally Posted by kilopi
Quote:
Originally Posted by Pinemarten
Quote:
As the comet approached, the ice in the nucleus began to evaporate (sublimate), and the comet soon became surrounded by a cloud of dust and gas (the "coma").
Doesn't sublimation occur when a solid changes phase directly to gas? Dry ice to CO2 for instance. Do comets melt to liquid for a short time before going to a gaseous state, or are they gas-ice, as opposed to water-ice?
Not sure what distinction you are making. Sublimation means to go from a solid to a gas without a liquid phase (or vice versa), but that is still evaporation (to change into a vapor).
I guess, he thought only stuff like dry-ice sublimates, but not water-ice.
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