6498 Ko

6498 Ko

Discovery
Discovered by	K. Endate, K. Watanabe
Discovery site	Kitami
Discovery date	October 26, 1992
Designations
MPC designation	1992 UJ4
Named after	Ko Nagasawa
Alternative names	1964 PM, 1971 QK3, 1994 CD4
Minor planet category	main-belt
Orbital characteristics
Epoch JD 2457200.5 (27 June 2015) T_jup = 3.574
Uncertainty parameter 0
Observation arc	60.71 yr (22,175 days)
Aphelion	2.66537 AU (Q)
Perihelion	1.89632 AU (q)
Semi-major axis	2.28085 AU (a)
Eccentricity	0.16859
Orbital period	3.44 yr (1258.17883 d)
Mean anomaly	280.22194° (M)
Inclination	7.99102°
Longitude of ascending node	149.63903°
Argument of perihelion	156.781506°
Earth MOID	0.884483 AU
Physical characteristics
Dimensions	5 km – 12 km
Rotation period	500 h
Absolute magnitude (H)	13.5

6498 Ko (1992 UJ₄) is a Main belt asteroid discovered on October 26, 1992 by Kin Endate and Kazuro Watanabe at the Kitami Observatory in eastern Hokkaidō, Japan. It has an exceptionally long rotation period of around 500 hours, and makes many close approaches to other large asteroids.

Close Approaches

Although 6498 Ko does not cross the orbit of any planet, it does make close approaches to other large asteroids. The most notable of these is 29 Amphitrite: 6498 Ko approached within 0.038 AU of it in 1915, and will come even closer in 2025 (0.012 AU) and in 2135 (0.009 AU). 6498 Ko also made a close encounter with asteroid Juno on November 14, 2009, at a distance of about 0.047 AU.