Eos, Transactions American Geophysical Union

Scientists, stargazers welcome Hale-Bopp


  • Michael Carlowicz


Visible to the naked eye in the northern hemisphere—and soon in the southern hemisphere as well—Comet Hale-Bopp has been dubbed the “comet of the century” by many folks who watch the night skies. The farthest comet ever discovered by amateurs, Hale-Bopp was 1000 times brighter than the legendary Halley's Comet was at the same point beyond the orbit of Jupiter.

As Hale-Bopp made its closest approach to Earth on March 22 and to the Sun on April 1, it generated a tail that stretched 10° across the sky in urban areas and as much as 30° at the darkest sites. The comet's nucleus is estimated to be about 30–40 km across, compared to the 5 km or smaller nuclei of most other comets.