Ursids
Ursids (URS) | |
---|---|
![]() Ursa Minor with the radiant of the Ursids marked in red | |
Parent body | 8P/Tuttle[1] |
Radiant | |
Constellation | Ursa Minor (near Kochab) |
Right ascension | 14h 36m [2] |
Declination | +75.3°[2] (Northern Hemisphere) |
Properties | |
Occurs during | December 17 – December 26[1] |
Date of peak | December 22[1] |
Velocity | 33[2] km/s |
Zenithal hourly rate | 10[1] |
See also: List of meteor showers |
The Ursid (URS) meteor activity begins annually around December 17 and runs for over a week, 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 start of the 20th century.[1] While there were sporadic observations after, the first coordinated studies of the shower didn't begin until Dr. A. Bečvář observed an outburst of 169 per hour in 1945.[1] Further observations in the 1970s and ongoing to current have established a relationship with comet 8P/Tuttle.[1] Peter Jenniskens and Esko Lyytinen discovered that outbursts could happen when comet Tuttle was at aphelion because some meteoroids get trapped in the 7/6 orbital resonance with Jupiter.
Technical information
Earlier observations described an average radiant of RA=217°, DEC=76°,[1] 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."[1]
References
- ^ a b c d e f g h i Gary W. Kronk. "Observing the Ursids". Meteor Showers Online. Archived from the original on 2013-07-24. Retrieved 2012-11-17.
- ^ a b c IMO Meteor Shower Calendar: Ursids (URS)
External links
- Gary Kronk's Meteor Showers Online - Ursids
- International Meteor Organisation Calendar - Fall 2005
- NASA Ursid Airborne Campaign (2008 + Java applet)
- 2011 Ursids Radio results (RMOB)
- Ursids at Constellation Guide
- v
- t
- e
- Andromedids
- Antihelion Source
- Aquariids
- eta Aquariids
- kappa Aquariids
- North delta Aquariids
- North iota Aquariids
- South iota Aquariids
- Southern Delta Aquariids
- tau Aquariids
- Aquilids
- South June Aquilids
- Arietids
- Daytime eps. Arietids
- Daytime May Arietids
- Aurigids
- alpha Aurigids
- delta Aurigids
- Nov. iota Aurigids
- Bootids (June Bootids)
- Canis-Minorids
- Cancrids (delta Cancrids)
- Capricornids
- alpha Capricornids
- Daytime Capri.-Sagitt.
- Carinids (eta Carinids)
- Cassiopeids (beta Cassiopeids)
- Centaurids
- Cetids
- omega Cetids
- pi Cetids
- Comae Berenicids
- Cygnids (kappa Cygnids)
- Doradids (gamma Doradids)
- Draconids
- Eridanids (eta Eridanids)
- Geminids (epsilon Geminids)
- Herculids (tau Herculids)
- Hydrids (sigma Hydrids)
- Leonids
- Leonis Minorids (Dec. Leonis Minorids)
- Lyrids
- eta Lyrids
- June Lyrids
- Monocerotids
- Normids (gamma Normids)
- Orionids
- Pegasids
- Perseids
- Daytime zeta Perseids
- September epsilon Perseids
- Phoenicids (July Phoenicids)
- Piscis Austrinids
- Puppids (pi Puppids)
- Puppid-Velids
- Quadrantids
- Scorpiids
- alpha Scorpiids
- North omega Scorpiids
- South omega Scorpiids
- Serpentids (kappa Serpentids)
- Sextantids (Daytime Sextantids)
- Taurids
- Ursids
- Virginids
- alpha Virginids
- gamma Virginids
- eta Virginids
- theta Virginids
- iota Virginids
- lambda Virginids
- mu Virginids
- pi Virginids
- psi Virginids
- March Virginids
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Meteor_falling_courtesy_NASA.gif/65px-Meteor_falling_courtesy_NASA.gif)
- January 4
- February 8
- February 10
- March 14
- April 17
- April 22–23
- April 26
- May 6
- June 7
- June 27
- July 13
- July 28–29
- July 30
- July 31 – August 1
- August 13
- September 1
- October 8
- October 10
- October 21
- October 22
- November 9
- November 12
- November 18
- November 21–22
- December 5–6
- December 13–14
- December 15
- December 22
- See also
- List of meteor showers