Comet Hale-Bopp: Encyclopedia II - Comet Hale-Bopp - Hale-Bopp becomes a Great Comet

Comet Hale-Bopp - Hale-Bopp becomes a Great Comet

Hale-Bopp became visible to the naked eye in the summer of 1996, and although its rate of brightening slowed considerably during the latter half on 1996, scientists were still cautiously optimistic that it would become very bright. It was too close to the Sun to be observable during December 1996, but when it reappeared in January 1997 it was already bright enough to be seen by anyone who looked for it, even from large cities with light-polluted skies.

The Internet was a growing phenomenon at the time, and numerous websites that tracked the comet's progress and provided daily images from around the world became extremely popular. The Internet played a large role in encouraging the unprecedented public interest in Hale-Bopp.

As the comet approached the Sun, it continued to brighten, shining at 2nd magnitude in February, and showing a growing pair of tails, the blue gas tail pointing straight away from the Sun and the yellowish dust tail curving away along its orbit. On March 9, a solar eclipse in Mongolia and eastern Siberia allowed observers there to see the comet in the daytime. Hale-Bopp had its closest approach to Earth on March 22, 1997.

As it passed perihelion on April 1, 1997, the comet had developed into a spectacular sight. It shone brighter than any star in the sky except Sirius, and its two tails stretched 30-40 degrees across the sky. The comet was visible well before the sky got fully dark each night, and while many great comets are very close to the Sun as they pass perihelion, Comet Hale-Bopp was visible all night to northern hemisphere observers.

As impressive as the comet was, it could have been much more impressive. Had it passed as close to Earth as Comet Hyakutake (C/1996 B2) did in 1996, then the comet's tail would have spanned the entire sky and it would have been brighter than the full moon. However, even though its closest approach to Earth was at a distance of 1.315 AU, a distance which would have rendered many lesser comets totally invisible, Hale-Bopp still spanned half the sky with its two tails, although the longest reaches of the tails were too faint to be visible to the naked eye.

Adapted from the Wikipedia article "Hale-Bopp becomes a Great Comet", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki