P/2007 R5 (SOHO)

P/2007 R5 (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
Orbital characteristics A
Aphelion 4.9903 AU
Perihelion 0.0570 AU
Semi-major axis 2.5237 AU
Eccentricity 0.9774
Orbital period 4.01 yr
Inclination 13.676°
Last perihelion September 7, 2011
September 11, 2007
Next perihelion 2015-Sep-04

Comet P/2007 R5 (SOHO), also designated P/1999 R1 and P/2003 R5, is the first periodic comet to be discovered using the automated telescopes of the SOHO (SOlar and Heliospheric Observatory) spacecraft.

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

  1. ↑ 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.
  2. ↑ Marsden, Brian (18 September 2007), "MPEC 2007-S16 : COMET P/1999 R1 = 2003 R5 = 2007 R5 (SOHO)", Minor Planet Electronic Circular (2007-S16)
  3. ↑ 3.0 3.1 3.2 "SOHO's new catch: its first officially periodic comet". European Space Agency. 25 September 2007. Retrieved 2007-11-19.
  4. ↑ Rainer Kracht (2011-09-07). "Recent comet discoveries 2123-2137". Yahoo Groups: SOHO Hunter. Retrieved 2011-09-11.
  5. ↑ Karl Battams (Jan 30, 2012). "The tale of a very shy comet...". Sungrazing Comets @ Navy.mil. Retrieved 2012-01-30.

External links