Dust particles form the first tail. The only force which affects these small particles in space is corpuscular radiation from the Sun itself. This radiation pushes the tiny dust particles in the direction from which they came, the way wind can blow rain droplets at an angle. Cometary dust particles can be thought of as billowing up from the comet's surface. Thus, this comet tail generally points back along the comet trajectory.
Ions (electrically charged particles), which first come from the nucleus as (neutral) gaseous particles, are swept into the second comet tail by interaction with the Interplanetary Magnetic Field (IMF). The IMF, or magnetic field of the sun, which is present everywhere in interplanetary space, sweeps past the comet nucleus and carries the ions with it to form the tail. Because of this special interaction with the IMF, this tail always points directly away from the Sun.
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Comets
Dust particles form the first tail. This comet tail generally points back along the comet path (so if the comet is traveling right, the dust tail extends to the left).
Ions (electrically charged particles), which first come from the nucleus as (neutral) gaseous particles, are swept into the second comet tail. Because of the special interaction with the Sun's magnetic field, this tail always points directly away from the Sun.
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Comets
The picture on the left shows a comet with its two tails.
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Comets
Last modified January 9, 2004 by Jennifer Bergman.
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