Hale-Bopp May Have Formed Near Neptune
From the Stardust List at NASA's JPL

Comet Hale-Bopp, which paraded across evening skies during the winter and early spring of 1997, may have formed in our solar system somewhere near Neptune, a team of astronomers announced today. If correct, this would be the first time scientists have been able to pin down the homeland of one of the solar system's icy wayfarers.

The conclusion was based on the first-ever measurement of a noble gas in a comet, which revealed the comet has an abundance of argon, said Alan Stern, leader of a team of researchers that announced the finding today at the American Astronomical Society's meeting in Rochester, NY. Stern directs the Southwest Research Institute's Space Studies Department, and is principal investigator of the team that analyzed Hale-Bopp.

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