322P/SOHO
Discovery | |
---|---|
Discovered by | Terry Lovejoy, Kazimieras Cernis, Bo Zhou, and Sebastian Hönig |
Discovery date | September 4, 1999 |
Alternative designations | P/1999 R1, P/2003 R5, P/2007 R5, P/2011 R4 |
Orbital characteristics A | |
Epoch | 2013-Jan-01 (JD 2456293.5) |
Observation arc | 16 years |
# of observations used | 299 |
Aphelion | 4.978257 AU |
Perihelion | 0.05338 AU |
Semi-major axis | 2.5158179 AU |
Eccentricity | 0.978783 |
Orbital period | 3.99 yr |
Inclination | 12.630° |
TJupiter | 2.346 |
Dimensions | ~100-200 m |
Comet total magnitude (M1) | 19.00 ± 0.09 |
Last perihelion |
September 7, 2011 September 11, 2007 |
Next perihelion | 2015-Sep-04 |
Comet 322P/SOHO, also designated P/1999 R1, P/2003 R5, P/2007 R5, and P/2011 R4, is the first periodic comet to be discovered using the automated telescopes of the SOHO (SOlar and Heliospheric Observatory) spacecraft, and second to be given a numbered designation, after 321P/SOHO.
The periodicity of P/2007 R5 was predicted by Sebastian F. Hönig, a German graduate student and prolific asteroid discoverer, in 2006.[1] The announcement of the new periodic comet was made after the predicted return was confirmed by SOHO and observer B. Zhou on 10 September 2007.[2] Out of approximately 1,350 SOHO-observed sungrazer comets, this is the first to be verified as a short-period comet; most sungrazers are long-period comets on near-parabolic orbits that do not repeat for thousands of years, if at all.
As it passed to within 7.9 million kilometres of the Sun, around .05 AU, it brightened by a factor of around a million. This is common behavior for a comet.[3]
P/2007 R5 is probably an extinct comet. Extinct comets are those that have expelled most of their volatile ice and have little left to form a tail or coma. They are theorized to be common objects amongst the celestial bodies orbiting close to the Sun. P/2007 R5 (SOHO) is probably only 100–200 meters in diameter.[3]
It was expected to return in September 2011,[3] and was recovered by B. Zhou on September 6, 2011.[4]
Discovery credit goes to Terry Lovejoy (Australia, 1999), Kazimieras Černis (Lithuania, 2003), and Bo Zhou (China, 2007).
The second periodic comet discovered by SOHO is P/2003 T12 (SOHO).[5]
References
- ↑ Jaggard, Victoria (2007-09-25). "Photo in the News: Sun Probe Spies New Periodic Comet". National Geographic News. National Geographic Society. Retrieved 2007-09-25.
- ↑ Marsden, Brian (18 September 2007), "MPEC 2007-S16 : COMET P/1999 R1 = 2003 R5 = 2007 R5 (SOHO)", Minor Planet Electronic Circular (2007-S16)
- 1 2 3 "SOHO's new catch: its first officially periodic comet". European Space Agency. 25 September 2007. Retrieved 2007-11-19.
- ↑ Rainer Kracht (2011-09-07). "Recent comet discoveries 2123-2137". Yahoo Groups: SOHO Hunter. Retrieved 2011-09-11.
- ↑ Karl Battams (Jan 30, 2012). "The tale of a very shy comet...". Sungrazing Comets @ Navy.mil. Retrieved 2012-01-30.
External links
- Orbital simulation from JPL (Java) / Ephemeris
- SOHO's first officially periodic comet
- SOHO Comets (view real-time images)