(118228) 1996 TQ66

(118228) 1996 TQ66
Discovered byJ. Chen
D. C. Jewitt
C. Trujillo
J. X. Luu
Discovery siteMauna Kea Obs.
Discovery date8 October 1996
(118228) 1996 TQ66
1996 TQ66
TNO[3] · plutino[4][5]
Orbital characteristics[3]
Epoch 1 July 2021 (JD 2459396.5)
Uncertainty parameter 2
Observation arc24.17 yr (8,828 d)
Aphelion44.219 AU
Perihelion34.535 AU
39.377 AU
247.10 yr (90,254 d)
0° 0m 14.4s / day
Physical characteristics
Mean diameter
185 km (est. at 0.09)[4]

(118228) 1996 TQ66 , prov. designation: 1996 TQ66, is a resonant trans-Neptunian object of the plutino population in the Kuiper belt, located in the outermost region of the Solar System. It was discovered on 8 October 1996, by American astronomers Jun Chen, David Jewitt, Chad Trujillo and Jane Luu, using the UH88 telescope at the Mauna Kea Observatories, Hawaii.[1][2] The very red object measures approximately 185 kilometers (110 miles) in diameter. As of 2021, it has not been named.

Orbit and classification[]

1996 TQ66 orbits the Sun at a distance of 34.5–44.2 AU once every 247 years and 1 month (90,254 days; semi-major axis of 39.38 AU). Its orbit has an eccentricity of 0.12 and an inclination of 15° with respect to the ecliptic.[3] The body's observation arc begins with its official discovery observation at the Mauna Kea Observatories on 8 October 1996.[2] It came to perihelion in 1998. As of 2021, it is at 35.6 AU from the Sun and has an apparent magnitude of 22.85. [8]

1996 TQ66 is a trans-Neptunian object and belongs to the plutino population,[4][5] a large group of objects named after their largest member, Pluto. These resonant trans-Neptunian objects stay in a 2:3 mean-motion orbital resonance with Neptune, orbiting exactly two times the Sun for every three orbits Neptune does and are therefore protected from the planets scattering effect. Plutinos form in inner rim of the Kuiper belt, a circumstellar disc of mostly non-resonant classical Kuiper belt objects.

Numbering and naming[]

This minor planet was numbered by the Minor Planet Center on 16 November 2005, receiving the number (118228) in the minor planet catalog (M.P.C. 55524).[9] As of 2021, it has not been named.[2] According to the established naming conventions, it will be given a mythological name associated with the underworld.[10]

Physical characteristics[]

1996 TQ66 has a very red surface color (RR) in the visible part of the spectrum, with B−V and V–R color indices of 1.190±0.020 and 0.660±0.030, respectively, for a combined B−R magnitude of 1.85.[4][6][7] A red surface color is typically associated with the presence of tholins, polymer-like organic compounds, formed by long exposures to solar and cosmic radiation.

Rotation period[]

In 1999, results of a photometric survey of Kuiper belt objects by Romanishin and Tegler were published in the Journal Nature. For 1996 TQ66, a brightness variation of no more than 0.22 in magnitude could be determined, which is indicative of a modestly irregular shape.[7][11] As of 2021, no rotational lightcurve for this object has been obtained from photometry. The body's rotation period, pole and actual shape remain unknown.[3][7]

Diameter and albedo[]

Based on a generic magnitude-to-diameter conversion, 1996 TQ66 measures approximately 185 kilometers (110 miles) in diameter, for an assumed albedo of 0.9 and an magnitude of 7.[4][12] According to Mike Brown, who estimates a mean-diameter of 186 km (120 mi), the object is too small for being considered a dwarf planet candidate ("probably not").[13]


  1. ^ a b "MPEC 1997-N09 : 1996 TQ66". Minor Planet Electronic Circular. Minor Planet Center. 7 July 1997. Retrieved 9 September 2021.
  2. ^ a b c d e "118228 (1996 TQ66)". Minor Planet Center. Retrieved 10 September 2021.
  3. ^ a b c d e "JPL Small-Body Database Browser: 118228 (1996 TQ66)" (2020-12-09 last obs.). Jet Propulsion Laboratory. Retrieved 10 September 2021.
  4. ^ a b c d e "List of Known Trans-Neptunian Objects". Johnston's Archive. 18 August 2020. Retrieved 10 September 2021.
  5. ^ a b "Orbit Fit and Astrometric record for 118228". Southwest Research Institute. Retrieved 10 September 2021.
  6. ^ a b c d e Belskaya, Irina N.; Barucci, Maria A.; Fulchignoni, Marcello; Dovgopol, Anatolij N. (April 2015). "Updated taxonomy of trans-neptunian objects and centaurs: Influence of albedo". Icarus. 250: 482–491. Bibcode:2015Icar..250..482B. doi:10.1016/j.icarus.2014.12.004. ISSN 0019-1035.
  7. ^ a b c d "LCDB Data for (118228)". Asteroid Lightcurve Database (LCDB). Retrieved 10 September 2021.
  8. ^ a b "Asteroid (118228) 1996 TQ66 – Ephemerides". AstDyS-2, Asteroids – Dynamic Site. Retrieved 10 September 2021.
  9. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 10 September 2021.
  10. ^ "Naming of Astronomical Objects – Minor planets". IAU – International Astronomical Union. Retrieved 27 July 2021.
  11. ^ Romanishin, W.; Tegler, S. C. (March 1999). "Rotation rates of Kuiper-belt objects from their light curves". Nature. 398 (6723): 129–132. Bibcode:1999Natur.398..129R. doi:10.1038/18168. ISSN 0028-0836.
  12. ^ "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 10 September 2021.
  13. ^ Brown, Michael E. "How many dwarf planets are there in the outer solar system?". California Institute of Technology. Retrieved 10 September 2021.

External links[]