2060 Chiron

2060 Chiron
95P/Chiron
	Hubble Space Telescope image of 2060 Chiron, taken in 2015.
Discovery
Discovered by	Charles Kowal
Discovery site	Palomar Observatory
Discovery date	1 November 1977
Designations
MPC designation	(2060) Chiron; 95P/Chiron;
Pronunciation	/ˈkaɪrɒn/
Named after	Chiron (Greek mythology)
Alternative designations	1977 UB
Minor planet category	centaur; comet; distant;
Adjectives	Chironian; Chironean; (both /kaɪˈroʊniən/);
Symbol	(astrological)
Orbital characteristics
	Epoch 2021-Jul-01 (JD 2459396.5)
	Uncertainty parameter 0
Observation arc	126.29 yr
Earliest precovery date	24 April 1895; (Harvard Observatory)
Aphelion	18.87 AU (2.8 billion km); (occurred May 2021)
Perihelion	8.533 AU (1.3 billion km)
Semi-major axis	13.70 AU (2.0 billion km)
Eccentricity	0.3772
Orbital period (sidereal)	50.71 yr (18,523 days)
Average orbital speed	7.75 km/s
Mean anomaly	180.70°
Mean motion	0° 1m 10.2s / day
Inclination	6.9299°
Longitude of ascending node	209.27°
Time of perihelion	3 August 2046; 14 February 1996 (previous); 29 August 1945; 16 March 1895;
Argument of perihelion	339.71°
Jupiter MOID	3.1 AU (460 million km)
Saturn MOID	0.48 AU (72 million km)
Uranus MOID	1.4 AU (210 million km)
TJupiter	3.363
Physical characteristics
Dimensions	126±22 km x 109±19 km x 68±12 km
Mean radius	116.7±7.3 km (Spitzer); 135.69 km (LCDB, derived); 98±17 km (Sickafoose 2023);
Synodic rotation period	5.918 h
Geometric albedo	0.057 (assumed); 0.15±0.03; 0.160±0.030;
Spectral type	B (Tholen), Cb (SMASS); B–V = 0.704; U–B = 0.283; BB; C;
Apparent magnitude	18.93; 14.9 (Perihelic opposition)
Absolute magnitude (H)	5.80±0.27; 5.82±0.07; 5.83; 5.92±0.20; 6.287±0.022 (R); 6.56; 6.79;
Angular diameter	0.035" (max)

2060 Chiron is a ringed small Solar System body in the outer Solar System, orbiting the Sun between Saturn and Uranus. Discovered in 1977 by Charles Kowal, it was the first-identified member of a new class of objects now known as centaurs—bodies orbiting between the asteroid belt and the Kuiper belt. Chiron is named after the centaur Chiron in Greek mythology.

Although it was initially called an asteroid and classified only as a minor planet with the designation "2060 Chiron", in 1989 it was found to exhibit behavior typical of a comet. Today it is classified as both a minor planet and a comet, and is accordingly also known by the cometary designation 95P/Chiron. More recently, a series of occultation events through the 2010s and early 2020s revealed that Chiron hosts rings, making it one of four minor planets and the only known comet to host a ring system.