(524366) 2001 XR254

Kuiper belt object August 2026 https://arxiv.org/abs/2607.27589 May 2019 yes (524366) 2001 XR 254 #C2E0FF (524366) 2001 XR254 hst.jpg Hubble Space Telescope image of 2001 XR 254 and its satellite, taken in 2007. D. C. JewittS. S. SheppardJ. Kleyna Mauna Kea Obs. 10 December 2001 (524366) 2001 XR 254 TNOcubewanocold 27 April 2019 (JD 2458600.5) 43 14.26 yr (5,207 d) 44.374 AU 41.178 AU ≈ 7 September 2120JPL Horizons Observer Location: @sun (Perihelion occurs when deldot changes from negative to positive. Uncertainty in time of perihelion is 3-sigma.)±1 month 42.776 AU 0.0374 279.78 yr (102,188 d) 226.02° 0.0035 ms / day 1.2309° 180.01° 78.868° 1 (D: 140 km; P: 125.58 d) 221 41 71 km (combined)171 32 55 km (primary) 4.055 0.048 18 kg 1.00 0.96 0.56 g/cm3Assuming that both components have equal albedos and equal densities V−I 1.06 0.12 0.136 0.168 0.044 5.76.05 (524366) 2001 XR 254 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 km mi off 2 us. 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. Discovery and orbit 2001 XR 254 was discovered on 10 December 2001 by David C. Jewitt, Scott S. Sheppard and Jan Kleyna using 2.2-meter University of Hawaii reflector on Mauna Kea. 2001 XR 254 belongs to the dynamically cold population of the classical Kuiper belt objects, with small orbital eccentricities and inclinations. Their semi-major axes reside mainly in the interval 40–45 AU. Satellite 2001 XR 254 is a binary consisting of two components of approximately equal size. Assuming that both components have the same albedo, the primary is estimated to be about 170 km in diameter. The size of the secondary (satellite) in this case is estimated at 140 km. The total mass of the system is about 418 kg. The average density of both components is about 1 g/cm3. + Orbital parameters of the 2001 XR 254 system Semi-major axis (km) Eccentricity Period (d) Inclination (°) 9311 ± 52 0.5561 ± 0.0047 125.579 ± 0.048 41.08 ± 0.22 Numbering and naming This minor planet was numbered by the Minor Planet Center on 18 May 2019 (M.P.C. 114619). As of 2025, it has not been named. Physical characteristics The surfaces of both components of 2001 XR 254 appear to have a neutral color. Notes lower-alpha References 30em 2016-03-13 last obs. JPL Small-Body Database Browser: (2001 XR254) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3102795 Jet Propulsion Laboratory 3 December 2018 2001 XR254 Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=2001+XR254 3 December 2018 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 29 May 2019 How many dwarf planets are there in the outer solar system? California Institute of Technology Brown Michael E. http://web.gps.caltech.edu/~mbrown/dps.html 3 December 2018 Asteroids with Satellites Database – 2001 XR254 Johnston's Archive 23 June 2015 Johnston Wm. Robert http://www.johnstonsarchive.net/astro/astmoons/am2001xr254.html 3 December 2018 Marc W. Buie Marc W. Buie Orbit Fit and Astrometric record for 01XR254 SwRI (Space Science Department) http://www.boulder.swri.edu/~buie/kbo/astrom/01XR254.html 2018-02-17 6 E. Vilenius C. Kiss M. Mommert T. Müller P. Santos-Sanz A. Pal J. Stansberry M. Mueller N. Peixinho S. Fornasier E. Lellouch A. Delsanti A. Thirouin J. L. Ortiz R. Duffard D. Perna N. Szalai S. Protopapa F. Henry D. Hestroffer M. Rengel E. Dotto P. Hartogh 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 2012A&A...541A..94V 10.1051/0004-6361/201118743 1204.0697 54222700 MPEC 2002-V07 : 2001 XR254, 2001 XS254, 2001 XU254 1 November 2002 Brian G. Marsden IAU Minor Planet Center Harvard-Smithsonian Center for Astrophysics https://www.minorplanetcenter.net/iau/mpec/K02/K02V07.html 3 December 2018 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. Mutual orbit orientations of transneptunian binaries Icarus December 2019 334 62–78 10.1016/j.icarus.2019.03.035 External links List of Transneptunian Objects, Minor Planet Center List of binary asteroids/TNOs, Johnston's Archive 524366 2001 XR254 524366 (524366) 2001 XR 254 524366 Category:Discoveries by David C. Jewitt Category:Discoveries by Scott S. Sheppard Category:Discoveries by Jan Kleyna 524366 20011210