This area will cover relevant news of the threat to the planet from Near Earth Objects (NEOs) including concepts and designs for mitigation. All opinions are those of the author.

25 October 2007

NEO News (10/25/07) Amazing Comet Holmes

Note: The following is the 10/25/07 Edition of NEO News, an email newsletter distributed by David Morrison.

NEO News (10/25/07) Amazing Comet Holmes

This is a special note to alert you to something you may want to see, especially if you have access to a small telescope.

Approximately 36 hours ago Comet Holmes (a normally inconspicuous Jupiter-family comet with aphelion at the orbit of Jupiter and perihelion at 2.2 AU) brightened by almost a million-fold. This is equivalent to the planet Saturn suddenly becoming as bright as the full moon. On October 23-24, Comet Holmes went from magnitude 17 to magnitude 2.8 in just a few hours, doubling in brightness every half hour. At its discovery in 1892, this comet also underwent a similar sudden brightening, presumably due to a very large ejection of gas and dust.

The comet is now easily visible to the naked eye as a bright yellow "star" in the constellation Perseus. For northern hemisphere observers, it can be seen almost all night, passing nearly overhead. A good source for the latest information is the Sky & Telescope webpage or at The best finding chart I have seen is on the Netherlands webpage

I looked at the comet about midnight last night from the balcony of my urban townhouse. It was about magnitude three, and at low telescopic power it was conspicuous as a bright yellowish disk, looking almost like a planet. At moderate power the disk resolved into a very bright inner coma and a slightly asymmetric fainter outer cloud, but no tail was visible. I have never before seen anything like it.

David Morrison

NEO News (now in its thirteenth year of distribution) is an informal compilation of news and opinion dealing with Near Earth Objects (NEOs) and their impacts. These opinions are the responsibility of the individual authors and do not represent the positions of NASA, the International Astronomical Union, or any other organization. To subscribe (or unsubscribe) contact For additional information, please see the website If anyone wishes to copy or redistribute original material from these notes, fully or in part, please include this disclaimer.

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