Comet Hale-Bopp

Date of the discovery: 23 July 1995

Short Description: The comet Hale-Bopp was perhaps the most widely observed comet of the 20th century and the brightest for many decades. It was visible with the naked eye for 18 months. While Alan Hale had a PhD and sent the discovery via E-Mail, Thomas Bopp sent the report via Telegram, which was unusual for this time. Comet Hale-Bopp is also called the Great Comet of 1997. One result of the intense observations was that the coma (envelope around the nucleus) had smaller dust grains than any other comet. The comet had a third tail, made out of Sodium. Usually comets only have a gas and a dust tail. Additionally it was found that the comet had an abundance of Deuterium (heavy water), which was twice as much as on earth. Organic chemicals were found and the rotation was measured to be 11 hours 46 minutes. It is not sure if this comet has an double nucleus or a single nucleus.

Amateur Astronomer(s): Alan Hale, Thomas Bopp

Link to paper in ADS:

Minor Planet Center:

Other pages:


Credit for the header image: E. Kolmhofer, H. Raab; Johannes-Kepler-Observatory, Linz, Austria

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