(9921) 1981 EO18

(9921) 1981 EO₁₈

Orbit of (9921) 1981 EO18 (blue), planets (red) and the Sun (black). The outermost planet visible is Jupiter.
Discovery
Discovered by	S. J. Bus
Discovery date	2 March 1981
Designations
MPC designation	(9921) 1981 EO18
Minor planet category	Main Belt asteroid
Orbital characteristics[1]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc	22681 days (62.10 yr)
Aphelion	2.5184972 AU (376.76182 Gm)
Perihelion	2.2347981 AU (334.32104 Gm)
Semi-major axis	2.3766477 AU (355.54144 Gm)
Eccentricity	0.0596847
Orbital period	3.66 yr (1338.3 d)
Mean anomaly	289.85012°
Mean motion	0° 16^m 8.41^s / day
Inclination	2.401065°
Longitude of ascending node	331.39626°
Argument of perihelion	89.15014°
Earth MOID	1.24767 AU (186.649 Gm)
Jupiter MOID	2.65114 AU (396.605 Gm)
Jupiter Tisserand parameter	3.537
Physical characteristics
Dimensions	~12.3 km[2]
Rotation period	8.01 h (0.334 d)
Geometric albedo	~0.01
Surface temp. min mean max Kelvin Celsius
Absolute magnitude (H)	14.3

(9921) 1981 EO₁₈ is a main belt asteroid. It orbits the Sun once every 3.67 years.^[1]

Discovered on March 2, 1981, by Schelte Bus at the Siding Spring Observatory, it was given the provisional designation "1981 EO₁₈".^[3]

References

1. "9921 Rubincam (1981 EO18)". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 13 April 2016.
2. Tedesco E.F.; Noah P.V.; Noah M.; Price S.D. "The supplemental IRAS minor planet survey (SIMPS)".
3. (9921) 1981 EO18 Minor Planet Center's Minor Planet Ephemeris Service

External links

• 9921 Rubincam at the JPL Small-Body Database

• Discovery · Orbit diagram · Orbital elements · Physical parameters