2015 KH163

2015 KH₁₆₃, is a trans-Neptunian- and scattered disc object from the outermost region of the Solar System, approximately 117 kilometers in diameter. It was first observed by astronomers during the Outer Solar System Origins Survey at the Mauna Kea Observatories on 24 May 2015.^[1][2][5]

2015 KH₁₆₃

Discovery[1][2]
Discovered by	OSSOS
Discovery site	Mauna Kea Obs.
Discovery date	24 May 2015
Designations
MPC designation	2015 KH163
Alternative designations	o5m85[3]
Minor planet category	TNO[4] · SDO[5] distant[1] · detached
Orbital characteristics[4]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 4
Observation arc	2.97 yr (1,085 days)
Aphelion	273.00 AU
Perihelion	40.068 AU
Semi-major axis	156.53 AU
Eccentricity	0.7440
Orbital period (sidereal)	1958.49 yr (715,337 days)
Mean anomaly	353.15°
Mean motion	0° 0m 1.8s / day
Inclination	27.079°
Longitude of ascending node	67.593°
Argument of perihelion	230.29°
Physical characteristics
Dimensions	117 km (calculated)[5]
Apparent magnitude	0.09 (assumed)[5]
Absolute magnitude (H)	7.9483[4]

Description

This minor planet is one of a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more.^[6] Such objects can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine.

Based on an absolute magnitude of approximately 7.95 and an assumed albedo of 0.09, the Johnston's Archive calculated a mean-diameter of 117 kilometers.^[5]

2015 KH₁₆₃ is located very near the 1:12 Neptune resonance of 157.8 AU (compared to its 157.2 ± 0.6 AU), meaning that it completes roughly 1 orbit for every 12 orbits Neptune makes.