Comets are huge mountains of ice and dust that travel around our Sun in orbits that are usually much more eccentric than the planetary orbits. They are thought to have formed nearly 5 billion years ago when our Solar System was born. A typical comet has three parts: a 1 to 30 mile diameter nucleus, a coma (halo), and the tail. The tail only appears when the comet comes into the inner solar system. As it hurtles in toward the Sun, the solar light and heat cause the outer layer of ice to sublimate, creating a diffuse and luminous cloud (halo) of gas and dust that surrounds the nucleus. Some of this gas and dust is driven away by the solar wind and by radiation pressure, forming a tail which can sometimes extend nearly one hundred million miles into space..
Comet Swift-Tuttle, which hurtled overhead during the Civil War, reappeared in the Fall of 1992.
This is the same image of Comet Swift-Tuttle, computer enhanced with color to show the extent of the halo surrounding the nucleus.
Comet DeVico, which appeared in October, 1995, had a tail that extended many millions of miles from the nucleus.
The same image of Comet DeVico, color enhanced by computer to show detail in brightness intensities.
Comet Hyakutake in a 10 second exposure taken on 3/23/96. Two days later, this comet made its closest approach to Earth at a distance of 9.3 million miles.
This is the same image of Comet Hyakutake, color enhanced by computer to show the extent of the tremendous halo that surrounded the nucleus.
Comet Hale-Bopp is one of the largest comets to visit the inner solar system in many, many years and may be one of the greatest comets of this century. This image is a 5 minute CCD exposure taken on 9/1/96.
Comet Hale-Bopp as it appeared over Kohl Observatory in March, 1997.
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