1961 Dufour

Dark main-belt asteroid October 2019 yes 1961 Dufour #D6D6D6 001961-asteroid shape model (1961) Dufour.png Modelled shape of Dufour from its lightcurve P. Wild Zimmerwald Obs. 19 November 1973 (1961) Dufour 1973 WA1927 UM1952 BQ 11962 YG1969 AH1973 SY 3 Henri Dufour (Swiss General) main-belt(outer) 4 September 2017 (JD 2458000.5) 0 54.20 yr (19,798 days) 3.5879 AU 2.7949 AU 3.1914 AU 0.1242 5.70 yr (2,082 days) 187.01° 0.1729 ms / day 6.6497° 29.581° 57.015° 50.25 km (derived)50.31 1.6 km (IRAS:20)51.15 0.98 km 15.7583 0.0309 h15.79 0.01 h 0.0335 (derived)0.039 0.0020.0402 0.003 (IRAS:20) C 10.6010.710.761 0.002 (R)10.8 1961 Dufour (prov. designation: 1973 WA) is a large background asteroid, approximately 50 km mi off 2 us in diameter, located in the outer region of the asteroid belt. It was discovered on 19 November 1973, by Swiss astronomer Paul Wild at Zimmerwald Observatory near Bern, Switzerland, and later named for 19th-century Swiss General Henri Dufour. Classification and orbit Dufour is a dark C-type asteroid, that orbits the Sun in the outer main-belt at a distance of 2.8–3.6 AU once every 5 years and 8 months (2,082 days). Its orbit has an eccentricity of 0.12 and an inclination of 7° with respect to the ecliptic. It was first identified as 1927 UM at Simeiz Observatory in 1927. The body's observation arc begins 21 years prior to its official discovery at Zimmerwald, when it was identified as 1952 BQ1 at McDonald Observatory in 1952. Naming This minor planet is named after Swiss General Henri Dufour (1787–1875), who lead the Swiss forces to victory against the renegade catholic cantons in the Sonderbund War of November 1847. The war claimed fewer than a 100 casualties. Dufour was also a co-founder of the International Committee of the Red Cross, founder of the Swiss Federal Office of Topography and architect of the first complete geodetic survey of Switzerland. The official 1961 naming citation was published by the Minor Planet Center on 18 April 1977 (M.P.C. 4157). The "Dufourspitze", the Alp's second-highest mountain after the Mont Blanc, was also named in his honour. Physical characteristics A two chord stellar occultation by the asteroid observed in 2004 gave an approximate diameter of 50 km.https://sbn.psi.edu/pds/resource/occ.html Asteroid Data Sets sbn.psi.edu 2018-05-26 French amateur astronomer Pierre Antonini obtained a lightcurve of Dufour from photometric observations taken during April 2010. Lightcurve analysis gave a well-defined rotation period of 15.79 0.01 hours with an amplitude of 0.31 in magnitude (U=3-). In August 2013, photometric observations at the Palomar Transient Factory, California, gave a similar period of 15.7583 0.0309 hours with a brightness variation of 0.35 (U=2). According to the surveys carried out by the Infrared Astronomical Satellite IRAS and the Japanese Akari satellite, Dufour measures 50.3 and 51.2 kilometers in diameter and its surface has an albedo of 0.040 and 0.039, respectively. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.034 and a diameter of 50.3 kilometers with an absolute magnitude of 10.8. References 2017-03-15 last obs. JPL Small-Body Database Browser: 1961 Dufour (1973 WA) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001961 Jet Propulsion Laboratory 2 July 2017 Dictionary of Minor Planet Names – (1961) Dufour Schmadel Lutz D. Springer Berlin Heidelberg (1961) Dufour 158 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1962 1961 Dufour (1973 WA) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1961 26 August 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 – (1961) Dufour Behrend Raoul Geneva Observatory http://obswww.unige.ch/~behrend/page4cou.html#001961 26 August 2016 3 August 2003 https://web.archive.org/web/20030803183423/http://obswww.unige.ch/~behrend/page4cou.html#001961 dead E. F. Tedesco P. V. Noah M. Noah S. D. Price October 2004 IRAS Minor Planet Survey V6.0 https://sbnarchive.psi.edu/pds3/iras/IRAS_A_FPA_3_RDR_IMPS_V6_0/data/diamalb.tab NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0 2004PDSS...12.....T 17 October 2019 1961 26 August 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 Adam Waszczak Chan-Kao Chang Eran O. Ofek Russ Laher Frank Masci David Levitan Jason Surace Yu-Chi Cheng Wing-Huen Ip Daisuke Kinoshita George Helou Thomas A. Prince Shrinivas Kulkarni September 2015 Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry The Astronomical Journal 150 3 35 2015AJ....150...75W 10.1088/0004-6256/150/3/75 1504.04041 External links Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20110721225144/http://www.minorplanet.info/lightcurvedatabase.html 21 July 2011 ) 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 1961 1960 Guisan 1961 1962 Dunant 001961 Category:Discoveries by Paul Wild (Swiss astronomer) Category:Named minor planets 19731119