(181902) 1999 RD215

(181902) 1999 RD₂₁₅ is a trans-Neptunian object of the scattered disc, approximately 148 kilometers in diameter. It was discovered on 6 September 1999, by American astronomers Chad Trujillo, Jane Luu, and David Jewitt at the Mauna Kea Observatories, Hawaii.^[2][3]

(181902) 1999 RD₂₁₅

Discovery[1][2]
Discovered by	C. Trujillo J. X. Luu D. C. Jewitt
Discovery site	Mauna Kea Obs.
Discovery date	6 September 1999
Designations
MPC designation	(181902) 1999 RD215
Alternative designations	1999 RD215
Minor planet category	TNO[1] · SDO[3][4] · distant[2]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 3[1] · 1[2]
Observation arc	8.03 yr (2,933 days)
Aphelion	204.40 AU
Perihelion	37.541 AU
Semi-major axis	120.97 AU
Eccentricity	0.6897
Orbital period (sidereal)	1330.58 yr (485,993 d)
Mean anomaly	7.8003°
Mean motion	0° 0m 2.52s / day
Inclination	25.990°
Longitude of ascending node	210.32°
Argument of perihelion	137.86°
Physical characteristics
Mean diameter	147 km[4] 148 km[5]
Geometric albedo	0.08 (estimate)[5] 0.09 (estimate)[4]
Absolute magnitude (H)	7.4[1] · 7.6[5]

Orbit and classification

1999 RD₂₁₅ orbits from the center of the Kuiper belt to well beyond into the scattered disc. It orbits the Sun at a distance of 37.5–204.4 AU once every 1330 years and 7 months (485,993 days; semi-major axis of 121 AU). Its orbit has an eccentricity of 0.69 and an inclination of 26° with respect to the ecliptic.^[1] The body's observation arc begins with its official discovery observation.^[2]

Diameter and albedo

According to Johnston's Archive and Michael Brown, 1999 RD₂₁₅ measures 147 and 148 kilometers in diameter, and its surface has an estimated albedo of 0.09 and 0.08, respectively.^[4][5]

See also

• List of Solar System objects by greatest aphelion