Ursids

Ursids

The Ursids meteor activity begins annually around December 17th and runs for a week plus, until the 25th or 26th. This meteor shower is named for its radiant point which is located near the star Beta Ursae Minoris (Kochab) in the constellation Ursa Minor.

History

The Ursids were probably discovered by William F. Denning who observed them for several years around the turn of the 20th century. While there were sporadic observations after, the first coordinated studies of shower didn't begin until Dr. A. Becvar in 1945. Further observations in the 1970s and ongoing to current have established a relationship with the Tuttle comet, which also has some controversy.

Technical info

Earlier observations described an average radiant of RA=217 deg, DEC=+76 deg, with maximum occurring at a solar longitude of 270.66 deg (about December 22), with the duration being established as December 17-24.

The Ursids have a particularly narrow stream, prompting veteran meteor observer, Norman W. McLeod, III (Florida) to comment that the Ursids "must be a compact stream like the Quadrantids. You have to be within 12 hours of maximum to see much."

A stronger than usual Ursids meteor shower is expected due to the return of comet 8P/Tuttle for December 22, 2007. [http://ursid.seti.org/WGNUrsids.pdf]

External links

* [http://meteorshowersonline.com/showers/ursids.html Gary Kronk's Meteor Showers Online - Ursids]
* [http://www.imo.net/calendar/2005/fall International Meteor Organisation Calendar - Fall]
* [http://ursid.seti.org NASA Ursid Airborne Campaign]


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