The orbit of 2008 KV42 is nearly perpendicular to the ecliptic.
|Discovered by||Mauna Kea Obs.
(uncredited: B. Gladman
J. J. Kavelaars, J.-M. Petit)
|Discovery site||Mauna Kea Obs.|
|Discovery date||31 May 2008 (first obs.)|
|MPC designation||2008 KV42|
|Distant · TNO
|Orbital characteristics |
|Epoch 16 February 2017 (JD 2457800.5)|
|Uncertainty parameter 3|
|Observation arc||5.35 yr (1,954 days)|
|266.24 yr (97,243 days)|
|0° 0m 13.32s / day|
|Uranus MOID||4.29 AU|
2008 KV42 (nicknamed Drac) is the first trans-Neptunian object (TNO) with a retrograde orbit to be discovered. Its 103° inclination and its retrograde motion suggest that it is the missing link between its source in the Hills 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 41 AU takes about 266 years to complete an orbit around the Sun.
The discovery was announced on July 16, 2008, by the Canada–France Ecliptic Plane Survey team led by Brett Gladman. An official name has not been chosen because the object has not been numbered; the discovery team nicknamed 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 object's 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 Hills 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.
2008 KV42 may even provide evidence of Planet Nine. The Kozai effect inside the mean-motion resonances with Planet Nine may cause a periodic exchange between its inclination and its eccentricity. When the elongated perpendicular centaurs get too close to a giant planet, orbits such as that of 2008 KV42 are created.
- "JPL Small-Body Database Browser: (2008 KV42)" (2013-10-06 last obs.). Jet Propulsion Laboratory. Retrieved 15 February 2017.
- "2008 KV42". Minor Planet Center. Retrieved 15 February 2017.
- Marc W. Buie (2008-07-08). "Orbit Fit and Astrometric record for 08KV42". SwRI (Space Science Department). Retrieved 2008-09-15.
- Akimasa Nakamura and bas (2 May 2009). "List of Damocloids (Oort cloud asteroids)". Lowell Observatory. Retrieved 15 February 2017.
- "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. 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: i > 60 (deg) and q > 15 (AU)". JPL Solar System Dynamics. Retrieved 2013-05-29.
- "MPC list of q>15 and i>60 (HiHq objects)". IAU Minor Planet Center.
- "Announcements – International Team of Astronomers Finds Missing Link". nrc.cnrc.gc.ca. National Research Council. September 4, 2008. Retrieved 26 July 2014.
- "Discovery of the First Retrograde Transneptunian Object".
- Batygin, Konstantin; Brown, Michael E. (20 January 2016). "Evidence for a distant giant planet in the Solar system". The Astronomical Journal. 151 (2): 22. Bibcode:2016AJ....151...22B. arXiv: . doi:10.3847/0004-6256/151/2/22. (called drac in reference)
- Brown, Mike (2016-02-12). "Why I believe in Planet Nine.". FindPlanetNine.com.