67P/Churyumov–Gerasimenko

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67P/Churyumov–Gerasimenko
Comet 67P Churyumov-Gerasimenko.jpg
Discovery
Discovered by Klim Ivanovych Churyumov (in Ukrainian) and
Svetlana Ivanova Gerasimenko
Designations
1982 VIII; 1982f;
1989 VI; 1988i;
1969 R1; 1969 IV;
1969h; 1975 P1;
1976 VII; 1975i
Orbital characteristics[1]
Epoch 2013-Dec-20 (JD 2456646.5)
Aphelion 5.6839 AU
Perihelion 1.2429 AU
3.4634 AU
Eccentricity 0.64113
6.45 yr
Inclination 7.0418°
Physical characteristics
Dimensions 4 km in diameter
Mass 3.14×1012± 0.21×1012[2] kg
Mean density
102 ± 9[2] kg/m³
0.46 m/s

Comet Churyumov–Gerasimenko, officially designated 67P/Churyumov–Gerasimenko, is a comet with a current orbital period of 6.45 years.[1] It is the destination of the European Space Agency's Rosetta spacecraft mission, launched on 2 March 2004,[3][4] which "woke up" from hibernation mode on 20 January 2014[5][6] to monitor the comet and select a suitable site for an attempted landing in November 2014 by its Philae lander. The comet will next come to perihelion (closest approach to the Sun) on August 13, 2015.[7][8][9]

Discovery[edit]

The comet was discovered by Klim Ivanovych Churyumov (in Ukrainian), who examined a photograph that had been exposed for periodic comet 32P/Comas Solà by Svetlana Ivanova Gerasimenko on September 11, 1969, at the Alma-Ata Astrophysical Institute. Churyumov found a cometary object near the edge of the plate, but assumed that this was Comas Solá.

After returning to his home institute in Kiev, Churyumov examined all the photographic plates more closely. About a month after the photograph was taken (October 22), he discovered that the object could not be Comas Solá, because it was about 1.8 degrees off the expected position. Further scrutiny produced a faint image of Comas Solá at its expected position on the plate, thus proving that the other object was a newly discovered comet.

Observations[edit]

As preparation for the Rosetta mission, Hubble Space Telescope pictures taken on March 12, 2003, were closely analyzed. An overall 3D model was constructed and computer-generated images created.[10] On 6 June 2014 water vapor was detected coming from 67P at a rate of roughly 1 liter/sec when Rosetta was 360,000km from the comet and the comet was 3.9AU from the Sun.[11][12]

Orbital history[edit]

Comets are regularly nudged from one orbit to another when they encounter Jupiter in close proximity. Before 1959, Churyumov–Gerasimenko's perihelion distance (closest approach to the Sun) was about 2.7 AU. In February 1959, a close encounter with Jupiter[13] moved its perihelion inward to about 1.3 AU, where it remains today.[9]

Gallery[edit]

References[edit]

  1. ^ a b "JPL Small-Body Database Browser: 67P/Churyumov-Gerasimenko". Jet Propulsion Laboratory. 2013-10-05 last observation. Retrieved 2014-01-21. 
  2. ^ a b Maquet; Colas; Jorda; Crovisier. "67P/Churyumov-Gerasimenko mass determination based on a new method for modeling non-gravitiational forces and accelerations.". http://www.lpi.usra.edu/. Lunar and Planetary Institute. Retrieved 11 December 2013. 
  3. ^ Krolikowska, Malgorzata (2003). "67P/Churyumov–Gerasimenko – potential target for the Rosetta mission". Acta Astronomica 53: 195–209. arXiv:astro-ph/0309130. Bibcode:2003AcA....53..195K. 
  4. ^ Agle, DC; Cook, Jia-Rui; Brown, Dwayne; Bauer, Markus (17 January 2014). "NASA Release = 2014-015 - Rosetta: To Chase a Comet". NASA. Retrieved 18 January 2014. 
  5. ^ Jordans, Frank (20 January 2014). "Comet-chasing probe sends signal to Earth". AP News. Retrieved 20 January 2014. 
  6. ^ Jordans, Frank (20 January 2014). "Scientists hope comet-chaser spacecraft wakes up". AP News. Retrieved 20 January 2014. 
  7. ^ Seiichi Yoshida (December 30, 2010). "67P/Churyumov-Gerasimenko". aerith.net. Retrieved 2012-02-09. 
  8. ^ "67P/Russell Orbit". Minor Planet Center. Retrieved 2014-06-17. 
  9. ^ a b Kazuo Kinoshita (2009-05-07). "67P past, present and future orbital elements". Comet Orbit. Retrieved 2009-04-25. 
  10. ^ "Hubble Assists Rosetta Comet Mission". Hubble Site. 5 September 2003. 
  11. ^ "First Detection of Water from 67P/C-G". Rosetta blog @ esa. 23 June 2014. Retrieved 2014-06-23.  Sungrazer Comets
  12. ^ Agle, DC; Brown, Dwayne; Bauer, Markus (June 30, 2014). "Rosetta's Comet Target 'Releases' Plentiful Water". NASA. Retrieved June 30, 2014. 
  13. ^ "JPL Close-Approach Data: 67P/Churyumov-Gerasimenko". 2010-06-29 last obs. Retrieved 2012-02-09. 

External links[edit]

Periodic comets (by number)
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