C/2010 X1 (Elenin)

C/2010 X1 (Elenin)
Comet Elenin as seen by the STEREO-B spacecraft on 1 August 2011
Discovery
Discovered byLeonid Elenin
0.45 m reflector (H15)
Discovery date10 December 2010
Orbital characteristics
Epoch31 March 2011
(JD 2455651.5)
Orbit typeOort cloud
Aphelion~97,000 AU (1.5 ly) (inbound)
Perihelion0.48242 AU
Semi-major axis~48,000 AU (inbound)
Eccentricity0.999990 (inbound)
1.000067 (near perihelion)
Orbital periodmillions of years (inbound)
Inclination1.8396°
Last perihelion10 September 2011
Physical characteristics
Mean radius
0.430±0.029 km
Mean density
450±60 kg/m3

Comet C/2010 X1 (Elenin) was an Oort cloud comet discovered by Russian amateur astronomer Leonid Elenin on 10 December 2010, through remote control of the International Scientific Optical Network's robotic observatory near Mayhill in the U.S. state of New Mexico. The discovery was made using the automated asteroids discovery program CoLiTec. At the time of discovery, the comet had an apparent magnitude of 19.5, which made it about 150,000 times fainter than can be seen with the naked eye. The discoverer, Leonid Elenin, originally estimated that the comet nucleus was 3–4 km in diameter, but more recent estimates place the pre-breakup size of the comet at 2 km. Comet Elenin started disintegrating in August 2011, and as of mid-October 2011 was not visible even using large ground-based telescopes.