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Originally Posted by Pinemarten
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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").
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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).