2015 TH₃₆₇

2015 TH₃₆₇
	Orbit and current position of 2015 TH367
Discovery
Discovered by	D. J. Tholen; S. S. Sheppard; C. W. Trujillo
Discovery site	Mauna Kea Obs.
Discovery date	13 October 2015; (first observed only)
Designations
MPC designation	2015 TH367
Alternative designations	V774104; (internal designation)
Minor planet category	TNO · SDO; distant
Orbital characteristics
	Epoch 2015-Dec-05 (JD 2457361.5)
	Uncertainty parameter 8
Observation arc	2.1 years using 10 observations
Aphelion	128±18 AU
Perihelion	29.3±1.2 AU
Semi-major axis	78±11 AU
Eccentricity	0.63±0.07
Orbital period (sidereal)	695±150 yr
Mean anomaly	66°±22°
Mean motion	0° 0m 4.716s / day
Inclination	10.99°±0.025°
Longitude of ascending node	245.1°±0.06°
Time of perihelion	≈1888±15?
Argument of perihelion	17°±7°
Neptune MOID	≈0.5 AU (75 million km)
Physical characteristics
Mean diameter	211 km (estimate); 220 km (est. at 0.09)
Geometric albedo	0.08 (assumed)
Apparent magnitude	26.2
Absolute magnitude (H)	6.6

2015 TH367 is a trans-Neptunian object approximately 220 kilometers (140 miles) in diameter. As of 2021 it is approximately 90 AU (13 billion km) from the Sun. At the time of its announcement in March 2018, it was the third most distant observed natural object in the Solar System, after Eris and 2014 UZ224.

At a visual apparent magnitude of 26.2, it is one of the faintest trans-Neptunian objects observed and only the largest telescopes in the world can observe it. Being so far from the Sun, 2015 TH₃₆₇ moves very slowly among the background stars and has only been observed eight times over 355 days. It requires an observation arc of several years to refine the uncertainties in the approximately 700-year orbital period and determine whether it is currently near or at aphelion (farthest distance from the Sun). As of 2023 the nominal JPL Horizons solution has it coming to aphelion around the year 2238, whereas Project Pluto (which only fit 5 of the 8 observations) shows it reached aphelion around 2015.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.