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This picture shows the two different tails of a comet - the dust tail and the ion tail.
Click on image for full size
JPL

The Comet Tail

A comet generally has two tails, not one. One tail is due to the comet's dust particles. The second is due to gas that comes from the comet coma.

The picture on the left shows a comet with its two tails.

Last modified January 9, 2004 by Jennifer Bergman.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA