(472651) 2015 DB216 explained

Minorplanet:yes
Background:
  1. C7FF8F
Discoverer:Mount Lemmon Survey (G96)
Discovered:February 27, 2015
Epoch:4 September 2017 (JD 2458000.5)
Uncertainty:2
Observation Arc:13.17 yr (4,812 days)
Perihelion:12.944 AU
Semimajor:19.211 AU
Eccentricity:0.3262
Period:84.20 yr (30,755 days)
Mean Motion: / day
Inclination:37.709°
Asc Node:6.2797°
Arg Peri:237.99°
Jupiter Moid:8.37627AU
Dimensions:44–160 km
Magnitude:20.8 (2015)
20.7 (2016)
19.4 (2029; peak)
Abs Magnitude:8.4

is a centaur and Uranus co-orbital discovered on February 27, 2015, by the Mount Lemmon Survey. It is the second known centaur on a horseshoe orbit with Uranus, and the third Uranus co-orbital discovered after (a Trojan) and 83982 Crantor (a horseshoe librator). A second Uranian Trojan,, was announced in 2017.

Description

An early orbital calculation of the asteroid with an observation arc of 10 days suggested an extremely close MOID to Neptune, but further observations on March 27 refined the orbit to show that the asteroid passes no less than several astronomical units away from Neptune, and show the orbit instead being that of a typical centaur, with a perihelion near that of Saturn, and traveling near to Uranus and Neptune. Later, observations suggested a distant orbit traveling extremely distant from the Sun, but now this too has been shown to be incorrect with later observations. However, it does have a semimajor axis near that of Uranus, making it a Uranus co-orbital. However it is not a Trojan, as it stays near the opposite side of the Sun from Uranus.

A paper, submitted on July 27, 2015, analyzed 's orbital evolution, and suggested that it may be more stable than the other known Uranus co-orbitals due to its high inclination, and that many more undiscovered Uranus co-orbitals may exist.

Precovery images from 2003 were located soon after 's discovery, giving it an 11-year observation arc.

See also

Notes

  1. Assuming an albedo from 0.05 (160 km) to 1 (40 km); is definitely somewhere within this range, and cannot be any smaller than 40 kilometers, assuming the absolute magnitude is correct.