1691 Oort

Rare-type carbonaceous Themistian asteroid October 2019 yes 1691 Oort #D6D6D6 1691Oort (Lightcurve Inversion).png Lightcurve-based 3D-model of Oort padding: 5px 0; line-height: 1.3em; 9 September 1956 K. ReinmuthI. Groeneveld Heidelberg Obs. (1691) Oort 1956 RB1945 TD1947 DA1950 PZ1950 RU1951 XW1955 MW1956 SD1964 DAA917 TD Jan Oort (astronomer) main-beltThemis 4 September 2017 (JD 2458000.5) 0 71.42 yr (26,086 days) 3.7153 AU 2.6084 AU 3.1618 AU 0.1750 5.62 yr (2,054 days) 240.25° 1.0860° 174.55° 232.69° 27.13 km (calculated)33.163 0.534 km33.644 0.26737.37 0.74 km 10.2684 0.0005 h10.2705 0.0004 h 0.053 0.0020.065 0.0110.0672 0.01500.10 (assumed) Tholen = CUCUB–V = 0.682U–B = 0.316 10.90 0.1210.95 1691 Oort, provisional designation 1956 RB, is a rare-type carbonaceous Themistian asteroid from the outer region of the asteroid belt, approximately 33 kilometers in diameter. It was discovered on 9 September 1956, by German astronomer Karl Reinmuth and Dutch astronomer Ingrid van Houten-Groeneveld at Heidelberg Observatory in south-west Germany. It was later named after Dutch astronomer Jan Oort. Orbit and classification is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. Oort orbits the Sun at a distance of 2.6–3.7 AU once every 5 years and 7 months (2,054 days). Its orbit has an eccentricity of 0.18 and an inclination of 1° with respect to the ecliptic. It was first identified as 1945 TD at Turku in 1945, extending body's observation arc by 14 years prior to its official discovery observation. Information about an earlier 1917-identification, A917 TD, is not available. Physical characteristics The dark C-type asteroid, classified as a rare intermediate CU-type in the Tholen taxonomy. Rotation period In February 2009, a rotational lightcurve of Oort was obtained from photometric observations taken by French amateur astronomer René Roy. It gave a well-defined rotation period of 10.2705 hours with a brightness variation of 0.38 magnitude (U=3). An international study from 2013, published a concurring, modeled period of 10.2684 hours (n.a.). Diameter and albedo According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Oort measures 33.64 and 37.37 kilometers in diameter, and its surface has an albedo of 0.065 and 0.053, respectively. The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 and calculates a diameter of 27.13 kilometers with an absolute magnitude of 10.95. Naming This minor planet was named in honor of Dutch astronomer Jan Oort (1900–1992), director of the Leiden Observatory (1945–1970), president of the International Astronomical Union (1958–1961), and a well-known authority on stellar statistics and galactic structure. He overturned the idea that the Sun was at the center of the Milky Way. The Oort cloud, the outermost gravitationally bound region of the Solar System, was also named after him. The official 1691 naming citation was published by the Minor Planet Center on 15 February 1970 (M.P.C. 3023). References 2017-03-17 last obs. JPL Small-Body Database Browser: 1691 Oort (1956 RB) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001691 Jet Propulsion Laboratory 6 June 2017 Dictionary of Minor Planet Names – (1691) Oort Schmadel Lutz D. Springer Berlin Heidelberg 134 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1692 (1691) Oort 1691 Oort (1956 RB) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1691 19 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 – (1691) Oort Behrend Raoul Geneva Observatory http://obswww.unige.ch/~behrend/page4cou.html#001691 19 December 2016 1 April 2019 https://web.archive.org/web/20190401181659/http://obswww.unige.ch/~behrend/page4cou.html#001691 dead 1691 19 December 2016 6 Fumihiko Usui Daisuke Kuroda Thomas G. Müller Sunao Hasegawa Masateru Ishiguro Takafumi Ootsubo Daisuke Ishihara Hirokazu Kataza Satoshi Takita Shinki Oyabu Munetaka Ueno Hideo Matsuhara Takashi Onaka October 2011 Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey Publications of the Astronomical Society of Japan 63 5 1117–1138 2011PASJ...63.1117U 10.1093/pasj/63.5.1117 (online, AcuA catalog p. 153) 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 J. Hanus M. Broz J. Durech B. D. Warner J. Brinsfield R. Durkee D. Higgins R. A. Koff J. Oey F. Pilcher R. Stephens L. P. Strabla Q. Ulisse R. Girelli November 2013 An anisotropic distribution of spin vectors in asteroid families http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2013A&A...559A.134H Astronomy and Astrophysics 559 19 2013A&A...559A.134H 10.1051/0004-6361/201321993 1309.4296 19 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 19 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 19 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/20241208174218/http://obswww.unige.ch/~behrend/page_cou.html 8 December 2024 – Observatoire de Genève, Raoul Behrend Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center 1691 1690 Mayrhofer 1691 1692 Subbotina 001691 Category:Discoveries by Karl Wilhelm Reinmuth Category:Discoveries by Ingrid van Houten-Groeneveld Category:Named minor planets Category:Jan Oort 001691 19560909