(20161) 1996 TR66

(20161) 1996 TR66
Discovered byD. C. Jewitt
C. Trujillo
J. X. Luu
J. Chen
Discovery siteMauna Kea Obs.
Discovery date8 October 1996
(20161) 1996 TR66
TNO[1] · twotino[2][3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 4
Observation arc12.04 yr (4,398 days)
Aphelion66.612 AU
Perihelion28.630 AU
47.621 AU
328.63 yr (120,032 d)
0° 0m 10.8s / day
Physical characteristics
Dimensions139 km[5]

(20161) 1996 TR66 is a trans-Neptunian object orbiting beyond Pluto in the Kuiper belt of the outermost Solar System, approximately 139 kilometers (86 miles) in diameter. It was discovered on 8 October 1996, by astronomers David Jewitt, Chad Trujillo, Jane Luu, and Jun Chen at the Mauna Kea Observatory, Hawaii, in the United States.[4] It was the first discovery of a twotino.

Orbit and classification[]

It orbits the Sun at a distance of 28.6–66.6 AU once every 328 years and 8 months (120,032 days). Its orbit has an eccentricity of 0.40 and an inclination of 12° with respect to the ecliptic.[1] Near perihelion, it comes closer to the Sun than Neptune does (29.7 AU). It has a semi-major axis (average distance from the Sun) near the edge of the classical belt.


1996 TR66 was the first twotino discovered. Twotinos stay in a 1:2 orbital resonance with Neptune, which means that for every one orbit a twotino makes, Neptune orbits two times. Both the Minor Planet Center and the Deep Ecliptic Survey list this trans-Neptunian object as a twotino.[2][3]

Numbering and naming[]

This minor planet was numbered by the Minor Planet Center on 9 January 2001.[6] As of 2018, it has not been named.[4]


  1. ^ a b c d e "JPL Small-Body Database Browser: 20161 (1996 TR66)" (2008-10-23 last obs.). Jet Propulsion Laboratory. Retrieved 26 May 2017.
  2. ^ a b "MPEC 2009-J35 :Distant Minor Planets (2009 MAY 29.0 TT)". Minor Planet Center. 8 May 2009. Retrieved 12 May 2009.
  3. ^ a b Marc W. Buie (27 November 2000). "Orbit Fit and Astrometric record for 20161". SwRI (Space Science Department). Retrieved 12 May 2009. using 22 observations
  4. ^ a b c "20161 (1996 TR66)". Minor Planet Center. Retrieved 28 February 2017.
  5. ^ "List of known trans-Neptunian objects". johnstonsarchive. Retrieved 28 February 2017.
  6. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 24 February 2018.

External links[]