1473 Ounas

Main-belt asteroid April 2018 yes 1473 Ounas #D6D6D6 22 October 1938 Y. Väisälä Turku Obs. (1473) Ounas 1938 UT1950 NZ1950 PB 1 Ounasjoki River(in Finland) main-belt(middle) 16 February 2017 (JD 2457800.5) 0 77.90 yr (28,452 days) 3.1862 AU 1.9623 AU 2.5743 AU 0.2377 4.13 yr (1,509 days) 19.843° 0.2386 ms / day 13.651° 216.52° 129.42° 17.62 km (derived)18.164 0.10920.032 km (dated) 16 h (dated)139.1 0.1 h139.1 0.5 h 0.0841 (dated)0.110 0.0180.1189 (derived) S 11.67 0.3211.711.8 1473 Ounas, provisional designation 1938 UT, is a stony asteroid, suspected tumbler and a slow rotator from the middle region of the asteroid belt, approximately 18 kilometers in diameter. It was discovered on 22 October 1938, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland. The asteroid was named after the Finnish Ounas river. Classification and orbit Ounas is a S-type asteroid that orbits the Sun in the central main-belt at a distance of 2.0–3.2 AU once every 4 years and 2 months (1,509 days). Its orbit has an eccentricity of 0.24 and an inclination of 14° with respect to the ecliptic. As no precoveries were taken, and no previous identifications were made, the body's observation arc begins with its official discovery observation at Turku in 1938. Physical characteristics In October 2012/13, a rotational lightcurve of Ounas was obtained from photometric observations by astronomers René Roy, Vladimir Benishek, Andrea Ferrero, Daniel Klinglesmith, Frederick Pilcher, Raoul Behrend and Petr Pravec. It gave a well-defined rotation period of 139.1 hours with a brightness variation of 0.6 magnitude (U=3/3). Ounas is a suspected "tumbler", which have a non-principal axis rotation (NPAR). According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 18.16 kilometers in diameter and its surface has an albedo of 0.11. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.1189 and a diameter of 17.62 kilometers with an absolute magnitude of 11.7. Naming This minor planet was named after the Ounas river, one of the principal rivers in Finland. The official 1473 naming citation was published by the Minor Planet Center on 20 February 1976 (M.P.C. 3928). References 2016-11-05 last obs. JPL Small-Body Database Browser: 1473 Ounas (1938 UT) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001473 Jet Propulsion Laboratory 16 December 2016 Dictionary of Minor Planet Names – (1473) Ounas Schmadel Lutz D. Springer Berlin Heidelberg 118 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1474 (1473) Ounas 1473 Ounas (1938 UT) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1473 16 December 2016 Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008) 2009 https://archive.org/details/dictionaryminorp2008schm limited Appendix – Publication Dates of the MPCs Schmadel Lutz D. Springer Berlin Heidelberg 221 978-3-642-01964-7 10.1007/978-3-642-01965-4 Asteroids and comets rotation curves – (1473) Ounas Behrend Raoul Geneva Observatory http://obswww.unige.ch/~behrend/page4cou.html#001473 16 December 2016 3 August 2003 https://web.archive.org/web/20030803183423/http://obswww.unige.ch/~behrend/page4cou.html#001473 dead 1473 16 December 2016 6 A. Mainzer T. Grav J. Masiero E. Hand J. Bauer D. Tholen R. S. McMillan T. Spahr R. M. Cutri E. Wright J. Watkins W. Mo C. Maleszewski November 2011 NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results The Astrophysical Journal 741 2 25 2011ApJ...741...90M 10.1088/0004-637X/741/2/90 1109.6407 6 Frederick Pilcher Vladimir Benishek Andrea Ferrero Daniel A. III Klinglesmith Petr Pravec Rene Roy Raoul Behrend July 2013 New Photometry of 1473 Ounas http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2013MPBu...40..126P The Minor Planet Bulletin 40 3 126–129 1052-8091 2013MPBu...40..126P 16 December 2016 6 Peter Veres Robert Jedicke Alan Fitzsimmons Larry Denneau Mikael Granvik Bryce Bolin Serge Chastel Richard J. Wainscoat William S. Burgett Kenneth C. Chambers Heather Flewelling Nick Kaiser Eugen A. Magnier Jeff S. Morgan Paul A. Price John L. Tonry Christopher Waters November 2015 Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V Icarus 261 34–47 2015Icar..261...34V 10.1016/j.icarus.2015.08.007 1506.00762 16 December 2016 6 Joseph R. Masiero T. Grav A. K. Mainzer C. R. Nugent J. M. Bauer R. Stevenson S. Sonnett August 2014 Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014ApJ...791..121M The Astrophysical Journal 791 2 11 2014ApJ...791..121M 10.1088/0004-637X/791/2/121 1406.6645 16 December 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 Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center 1473 1472 Muonio 1473 1474 Beira 001473 Category:Discoveries by Yrjö Väisälä Category:Named minor planets 001473 19381022