We can observe two types of comet tail that reflect the light spectrum differently. One is a plasma trail, which draws a straight line like a broomstick. The other is a dust tail, which opens like the bristles on a broom. The plasma tail comprises electrons and ions that are ionized by the sun's ultraviolet radiation. The dust tail consists of micron-scale particles (1 micron = 1/1,000th mm).

The dust tail is wide and slightly bent because of the pressure of the light from the sun and the orbital action of the comet's nucleus.