(524366) 2001 XR254, provisional designation 2001 XR254, is a trans-Neptunian object and binary system from the classical Kuiper belt, located in the outermost region of the Solar System. The cubewano belongs to the cold population and measures approximately 171 kilometers (110 miles).[8] It was first observed on 10 December 2001, by astronomers at the Mauna Kea Observatory, Hawaii. Its 140-kilometer sized companion was discovered by the Hubble Space Telescope in June 2006.[7]
| Hubble Space Telescope image of 2001 XR254 and its satellite, taken in 2007. | |
| Discovery[1][2] | |
|---|---|
| Discovered by | D. C. Jewitt S. S. Sheppard J. Kleyna |
| Discovery site | Mauna Kea Obs. |
| Discovery date | 10 December 2001 |
| Designations | |
| (524366) 2001 XR254 | |
| 2001 XR254 | |
| TNO[3] · cubewano[4][2] cold[5] | |
| Orbital characteristics[3] | |
| Epoch 27 April 2019 (JD 2458600.5) | |
| Uncertainty parameter 4 · 3[1] | |
| Observation arc | 14.26 yr (5,207 d) |
| Aphelion | 44.374 AU |
| Perihelion | 41.178 AU |
| 42.776 AU | |
| Eccentricity | 0.0374 |
| 279.78 yr (102,188 d) | |
| 226.02° | |
| 0° 0m 12.6s / day | |
| Inclination | 1.2309° |
| 180.01° | |
| ≈ 7 September 2120[6] ±1 month | |
| 78.868° | |
| Known satellites | 1 (D: 140 km; P: 125.58 d)[7][8] |
| Physical characteristics | |
| 221+41 −71 km (combined) 171+32 −55 km (primary) | |
| Mass | (4.055±0.048)×1018 kg[9] |
Mean density | 1.00+0.96 −0.56 g/cm3[8][a] |
| 0.136+0.168 −0.044[8] | |
| V−I = 1.06±0.12[7] | |
| 5.7[1][3] 6.05[8] | |
| Semi-major axis (km) | Eccentricity | Period (d) | Inclination (°) |
| 9311 ± 52 | 0.5561 ± 0.0047 | 125.579 ± 0.048 | 41.08 ± 0.22 |
- ^ Assuming that both components have equal albedos and equal densities
- ^ a b c “2001 XR254”. Minor Planet Center. Retrieved 3 December 2018.
- ^ a b c Marsden, Brian G. (1 November 2002). “MPEC 2002-V07 : 2001 XR254, 2001 XS254, 2001 XU254”. IAU Minor Planet Center. Harvard-Smithsonian Center for Astrophysics. Retrieved 3 December 2018.
- ^ a b c “JPL Small-Body Database Browser: (2001 XR254)” (2016-03-13 last obs.). Jet Propulsion Laboratory. Retrieved 3 December 2018.
- ^ Marc W. Buie. “Orbit Fit and Astrometric record for 01XR254”. SwRI (Space Science Department). Retrieved 17 February 2018.
- ^ Brown, Michael E. “How many dwarf planets are there in the outer solar system?”. California Institute of Technology. Retrieved 3 December 2018.
- ^ JPL Horizons Observer Location: @sun (Perihelion occurs when deldot changes from negative to positive. Uncertainty in time of perihelion is 3-sigma.)
- ^ a b c Johnston, Wm. Robert (23 June 2015). “Asteroids with Satellites Database – 2001 XR254”. Johnston’s Archive. Retrieved 3 December 2018.
- ^ a b c d e f g h Vilenius, E.; Kiss, C.; Mommert, M.; Müller, T.; Santos-Sanz, P.; Pal, A.; et al. (May 2012). ““TNOs are Cool”: A survey of the trans-Neptunian region. VI. Herschel/PACS observations and thermal modeling of 19 classical Kuiper belt objects”. Astronomy and Astrophysics. 541: 17. arXiv:1204.0697. Bibcode:2012A&A…541A..94V. doi:10.1051/0004-6361/201118743. S2CID 54222700.
- ^ a b Grundy, W.M.; Noll, K.S.; Roe, H.G.; Buie, M.W.; Porter, S.B.; Parker, A.H.; Nesvorný, D.; Levison, H.F.; Benecchi, S.D.; Stephens, D.C.; Trujillo, C.A. (December 2019). “Mutual orbit orientations of transneptunian binaries”. Icarus. 334: 62–78. doi:10.1016/j.icarus.2019.03.035.
- ^ “MPC/MPO/MPS Archive”. Minor Planet Center. Retrieved 29 May 2019.
- List of Transneptunian Objects, Minor Planet Center
- List of binary asteroids/TNOs, Johnston’s Archive
- (524366) 2001 XR254 at AstDyS-2, Asteroids—Dynamic Site
- (524366) 2001 XR254 at the JPL Small-Body Database