|Discovered by||Brett J. Gladman, John J. Kavelaars, Jean-Marc Petit|
|Discovery date||May 31, 2008|
|Epoch August 22, 2008 (JD 2454700.5)|
|Aphelion||70.595 AU (10,560.800 Gm)|
|Perihelion||20.330 AU (3,041.293 Gm)|
|45.462 AU (6,801.047 Gm)|
|306.54 a (111,962.845 d)|
Average orbital speed
2008 KV42 (nicknamed Drac) is the first trans-Neptunian object (TNO) with a retrograde orbit to be discovered. Its 104° inclination and its retrograde motion suggest that it is the missing link between its source in the inner Oort cloud and Halley-type comets, thus providing further insight into the evolution of the outer Solar System. The object measures no more than 90 km across and with a semi-major axis of 45.462 AU takes a little over 306 years to complete an orbit around the Sun.
The discovery of the object was announced on July 16, 2008, by the Canada France Ecliptic Plane Survey team led by Brett Gladman. An official name has yet to be chosen by the International Astronomical Union (IAU); the discovery team nicknamed it 2008 KV42 "Drac" after Count Dracula.
Discovery and naming
The discovery of 2008 KV42 was announced on July 16, 2008 by the Canada France Ecliptic Plane Survey team led by Brett Gladman from the University of British Columbia. The announcement was made during the "Asteroids, Comets, Meteors" meeting held in Baltimore, Maryland, followed by a Minor Planet Electronic Circular on the same day and a IAU Circular on July 18. The discovery was made using images obtained on May 31 from the 3.5 meter Canada-France-Hawaii Telescope, followed by further observations until July 8 from the Whipple Observatory and Cerro Tololo.
2008 KV42 is the first trans-Neptunian object (TNO) with a retrograde orbit to be discovered. With a semi-major axis of 46±5 AU, it was discovered while at a distance of 32 AU and has a perihelion at roughly the distance of Uranus. The objects 104-degree inclination makes its almost perpendicular to the ecliptic, and is, as of July 2014, one of only five objects known to have inclination (i) > 60° and perihelion (q) > 15 AU.[nb 1] Its unusual orbit suggests that 2008 KV42 may have been perturbed inwards from its source, most likely in the inner Oort cloud, by an unknown gravitational disturbance. Its discovery may reveal the source regions for Halley-type comets which also have an retrograde orbit, but their origin remains unknown. 2008 KV42 itself is believed to be in an intermediate stage towards becoming a comet, thus helping to further explain the formation and evolution of the outer Solar System.
- The other four being: 2007 BP102, 2010 WG9, 2011 KT19 and (127546) 2002 XU93.
- Marc W. Buie (2008-07-08). "Orbit Fit and Astrometric record for 08KV42". SwRI (Space Science Department). Retrieved 2008-09-15.
- Akimasa Nakamura (18 Jul 2008). "Table of Damocloid objects, or Oort cloud asteroids". Lowell Observatory. Retrieved 2008-09-16.
- "Discovery of the retrograde trans-neptunian object 2008 KV42". cfeps.net. Canada France Ecliptic Plane Survey. 2008. Retrieved 23 July 2014.
- "Absolute Magnitude (H)". NASA/JPL. Archived from the original on 17 December 2009. Retrieved 2009-12-21.
- "A Retrograde TNO : 2008 KV42". cfeps.net. Canada France Ecliptic Plane Survey. 2008. Retrieved 23 July 2014.
- Hecht, Jeff (September 5, 2008). "Distant object found orbiting Sun backwards". newscientist.com. New Scientist. Retrieved 23 July 2014.
- "MPEC 2008-O02 : 2008 KV42". minorplanetcenter.net. Minor Planet Center. July 16, 2008. Retrieved 23 July 2014.
- "Circular No. 8960". cbat.eps.harvard.edu. Central Bureau for Astronomical Telegrams. July 18, 2008. Retrieved 23 July 2014.
- O'Neill, Ian (September 5, 2008). "Kuiper Belt Object Travelling the Wrong-Way in a One-Way Solar System". universetoday.com. Universe Today. Retrieved 24 July 2014.
- "JPL Small-Body Database Search Engine". ssd.jpl.nasa.gov. Retrieved 26 July 2014.
- "Announcements - International Team of Astronomers Finds Missing Link". nrc.cnrc.gc.ca. National Research Council. September 4, 2008. Archived from the original on December 25, 2013. Retrieved 26 July 2014.