(6491) 1991 OA

Highly eccentric stony asteroid October 2019 yes (6491) 1991 OA #FFC2E0 16 July 1991 H. E. Holt Palomar Obs. (6491) 1991 OA NEOAmorPHA 4 September 2017 (JD 2458000.5) 0 24.35 yr (8,895 days) 3.9772 AU 1.0227 AU 2.5000 AU 0.5909 3.95 yr (1,444 days) 215.03° 0.2493 ms / day 5.9464° 301.90° 323.60° 0.0420 AU16.4 LD 0.52 km (derived) 2.69 h 0.20 (assumed) S 18.7718.9 (6491) 1991 OA is a highly eccentric, stony asteroid, classified as a near-Earth object and potentially hazardous asteroid, approximately half a kilometer in diameter. It was discovered on 16 July 1991, by American astronomer Henry E. Holt at the U.S. Palomar Observatory in California. Orbit and classification The S-type body is an Amor asteroid – a subgroup of near-Earth asteroids that approach the orbit of Earth from beyond, but do not cross it. It orbits the Sun at a distance of 1.0–4.0 AU once every 3 years and 11 months (1,444 days). Its orbit has an eccentricity of 0.59 and an inclination of 6° with respect to the ecliptic. Its minimum orbit intersection distance (MOID) with Earth is 0.0420 AU, and on 1 August 2086, it will make a close approach and pass by Earth at a distance of 0.09 AU km on off. A first precovery was taken at the Australian Siding Spring Observatory in March 1991, extending the asteroid's observation arc by 4 months prior to its discovery. Physical characteristics In 2000, a rotational lightcurve was published from photometric observations obtained by the Near-Earth Objects Follow-up Program during the early 1990s. The lightcurve rendered a rotation period of 2.69 hours with an brightness amplitude of 0.08 in magnitude (U=2). The Collaborative Asteroid Lightcurve Link (CALL) assumes an albedo of 0.20 and derives a diameter of 0.53 kilometers, based on an absolute magnitude of 18.77. Naming As of 2017, 1991 OA remains unnamed. References 30em 2015-07-25 last obs. JPL Small-Body Database Browser: 6491 (1991 OA) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2006491 Jet Propulsion Laboratory 26 May 2017 6491 (1991 OA) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=6491 24 July 2016 6491 24 July 2016 2011-09-29 last obs JPL Close-Approach Data: 6491 (1991 OA) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=6491;cad=1#cad 24 March 2012 6 A. Erikson S. Mottola J. S. V. Lagerros M. Lindgren J. Piironen T. Oja G. Hahn C.-I. Lagerkvist A. W. Harris A. Nathues G. Neukum October 2000 The Near-Earth Objects Follow-up Program. III. 32 Lightcurves for 12 Objects from 1992 and 1995 http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2000Icar..147..487E Icarus 147 2 487–497 2000Icar..147..487E 10.1006/icar.2000.6457 1 January 2016 External links Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html 16 December 2017 ) Dictionary of Minor Planet Names, Google books Asteroids and comets rotation curves, CdR https://web.archive.org/web/20160729213840/http://obswww.unige.ch/~behrend/page_cou.html 29 July 2016 – Observatoire de Genève, Raoul Behrend 6491 6491 1991OA (6490) 1991 NR2 6491 (6492) 1991 OH1 006491 Category:Discoveries by Henry E. Holt 006491 19910716