1208 Troilus

Asteroid sharing Jupiter's orbit June 2018 yes 1208 Troilus #C2FFFF 1208 Troilus Hubble.jpg Hubble Space Telescope image of Troilus taken in 2012 K. Reinmuth Heidelberg Obs. 31 December 1931 (1208) Troilus 1931 YA1965 WK Troilian ˈ t r oʊ ə l ə s ,_ ˈ t r ɔɪ l ə sNoah Webster (1884) A Practical Dictionary of the English LanguageTroilus Troilus (Greek mythology) Jupiter trojanTrojanbackground 23 March 2018 (JD 2458200.5) 0 86.40 yr (31,557 d) 5.7305 AU 4.7712 AU 5.2509 AU 0.0913 12.03 yr (4,395 d) 189.17° 0.0819 ms / day 33.542° 48.546° 296.06° 0.001 AU 2.6590 100.48 1.10 km103.31 km (derived)103.34 3.9 km111.36 2.36 km 24 h56.17 0.07 h63.8 0.5 h 0.037 0.0020.0397 (derived)0.041 0.0060.0419 0.003 FCU (Tholen)C0 (Barucci)U–B 0.314 093B–V = 0.750 0.050V–R = 0.380 0.030V–I = 0.740 0.020 8.999.059.08 1208 Troilus ˈ t r oʊ ə l ə s is a large and notably inclined Jupiter trojan from the Trojan camp, approximately 103 km mi off us in diameter. It was discovered on 31 December 1931, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southern Germany. The unusual F-type asteroid belongs to the largest Jupiter trojans and has a long rotation period of 56.2 hours. It was named after the Trojan prince Troilus, who was killed by Achilles. Orbit and classification Troilus is a dark Jovian asteroid orbiting in the trailing Trojan camp at Jupiter's Lagrangian point, 60° behind its orbit in a 1:1 resonance. It is also a non-family asteroid of the Jovian background population. It orbits the Sun at a distance of 4.8–5.7 AU once every 12 years (4,395 days; semi-major axis of 5.25 AU). Its orbit has an eccentricity of 0.09 and a high inclination of 34° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Heidelberg in December 1931. Physical characteristics In the Tholen classification, Troilus has an ambiguous and unusual spectrum, closest to that of an F-type and somewhat similar to a common C-type asteroid (FCU). It has also been characterized as a carbonaceous C-type in the Barucci taxonomy (C0-type). Rotation period In April 2007, a rotational lightcurve of Troilus was obtained from photometric observations by Lawrence Molnar at the Calvin-Rehoboth Robotic Observatory G98 in New Mexico. Lightcurve analysis gave a rotation period of 56.17 0.07 hours with a brightness variation of 0.20 0.02 magnitude (U=2). While not being a slow rotator, Troilus has a significantly longer period than most asteroids, and one of longest of all larger Jupiter trojans. The period also supersedes previous observations made by Linda French with the 0.9-meter SMARTS telescope at Cerro Tololo in the 1980s and by Federico Manzini at the Sozzago Astronomical Station A12, which gave a period of 24 and 63.8 hours, respectively (U=2/1). Diameter and albedo According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Troilus measures between 100.48 and 111.36 kilometers in diameter and its surface has an albedo between 0.037 and 0.0419. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0397 and a diameter of 103.31 kilometers based on an absolute magnitude of 9.05. Naming This minor planet was named from Greek mythology after the young Trojan prince Troilus, the son of King Priam (also see 884 Priamus), who in a medieval legend loved Cressida (see 548 Kressida) and lost her to Diomedes (see 1437 Diomedes). Troilus was killed by Achilles (see 588 Achilles) in the Trojan War. The official naming citation was published by Paul Herget in The Names of the Minor Planets in 1955 (H 112). References 30em 2018-05-25 last obs. JPL Small-Body Database Browser: 1208 Troilus (1931 YA) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001208 Jet Propulsion Laboratory 12 June 2018 Schmadel Lutz D. Dictionary of Minor Planet Names Springer Berlin Heidelberg 101 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1209 (1208) Troilus 1208 Troilus (1931 YA) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1208 12 June 2018 List of Jupiter Trojans Minor Planet Center 30 May 2018 https://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html 6 June 2018 Asteroids and comets rotation curves – (1208) Troilus Behrend Raoul Geneva Observatory http://obswww.unige.ch/~behrend/page3cou.html#001208 3 August 2017 23 April 2019 https://web.archive.org/web/20190423121547/http://obswww.unige.ch/~behrend/page3cou.html#001208 dead T. Grav A. K. Mainzer J. M. Bauer J. R. Masiero C. R. Nugent November 2012 WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy The Astrophysical Journal 759 1 10 2012ApJ...759...49G 10.1088/0004-637X/759/1/49 1209.1549 119101711 (online catalog) Asteroid (1208) Troilus – Proper elements AstDyS-2, Asteroids – Dynamic Site https://newton.spacedys.com/astdys/index.php?n=1208&pc=1.1.6 12 June 2018 Asteroid 1208 Troilus Small Bodies Data Ferret https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1208+Troilus 12 June 2018 13 June 2018 https://web.archive.org/web/20180613014822/https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1208%20Troilus dead 1208 12 June 2018 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 free (online, AcuA catalog p. 153) 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 12 IRAS-A-FPA-3-RDR-IMPS-V6.0 2004PDSS...12.....T 15 June 2018 French, L. M. November 1987 Rotation properties of four L5 Trojan asteroids from CCD photometry http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=1987Icar...72..325F Icarus 72 2 325–341.MIT–supportedresearch 0019-1035 1987Icar...72..325F 10.1016/0019-1035(87)90178-3 22 November 2015 Molnar, Lawrence A. Haegert, Melissa J. Hoogeboom, Kathleen M. June 2008 Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2008MPBu...35...82M The Minor Planet Bulletin 35 2 82–84 1052-8091 2008MPBu...35...82M 22 November 2015 Martha W. Schaefer Bradley E. Schaefer David L. Rabinowitz Suzanne W. Tourtellotte June 2010 Phase curves of nine Trojan asteroids over a wide range of phase angles Icarus 207 2 699–713 2010Icar..207..699S 10.1016/j.icarus.2009.11.031 0912.1888 118589399 Joseph P. Chatelain Todd J. Henry Linda M. French Jennifer G. Winters David E. Trilling June 2016 Photometric colors of the brightest members of the Jupiter L5 Trojan cloud Icarus 271 158–169 2016Icar..271..158C 10.1016/j.icarus.2016.01.026 free 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 1208 1207 Ostenia 1208 1209 Pumma 001208 Category:Discoveries by Karl Wilhelm Reinmuth Category:Named minor planets 001208 19311231