4902 Thessandrus is a Jupiter trojan from the Greek camp , approximately 60 kilometers (37 miles) in diameter. It was discovered on 9 January 1989, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California, and later named after Thessander (Thessandrus) from Greek mythology .[ 2] D-type asteroid is an exceptionally slow rotator and tumbler . It belongs to the 70 largest Jupiter trojans .
Orbit and classification
Thessandrus is a dark Jovian asteroid orbiting in the leading Greek camp at Jupiter's L4 Lagrangian point , 60° ahead of the Gas Giant's orbit in a 1:1 resonance (see Trojans in astronomy ) .[ 4] family asteroid in the Jovian background population .[ 5]
It orbits the Sun at a distance of 5.0–5.4 AU once every 11 years and 10 months (4,337 days; semi-major axis of 5.2 AU). Its orbit has an eccentricity of 0.04 and an inclination of 9° with respect to the ecliptic .[ 3]
A first precovery was taken at the discovering observatory in 1954, extending the body's observation arc by 35 years prior to its official discovery observation.[ 1]
Physical characteristics
Thessandrus has been characterized as a D-type asteroid by Pan-STARRS ' survey.[ 7] [ 10] SDSS -based taxonomy.[ 11]
Slow rotator
In February 2013, a rotational lightcurve of Thessandrus was obtained from photometric observations by American astronomer Robert Stephens at the Center for Solar System Studies (U81 rotation period of ± 20magnitude (U=2 [ 9] slowest rotators known to exist.
Tumbler
The astronomers also detected a non-principal axis rotation seen in distinct rotational cycles in successive order. This is commonly known as tumbling .[ 9] Thessandrus is the fourth-largest asteroid and largest Jupiter trojan known to be is such a state (also see List of tumblers ).
Diameter and albedo
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer , Thessandrus measures between 51.26 and 71.79 kilometers in diameter and its surface has an albedo between 0.060 and 0.081.[ 6] [ 8]
The Collaborative Asteroid Lightcurve Link assumes a standard albedo of a carbonaceous asteroid of 0.057 and calculates a diameter of 61.04 kilometers based on an absolute magnitude of 9.8.[ 7]
100+ largest Jupiter trojans
Naming
This minor planet is named after Thessander (Thessandrus) from Greek mythology and Homer's Iliad . Together with 30 other Greek soldiers he hid in the Trojan horse 's belly.[ 2] Minor Planet Center on 4 June 1993 (M.P.C. 22248[ 12]
References
^ a b c d "4902 Thessandrus (1989 AN2)" . Minor Planet Center . Retrieved 17 June 2018 .^ a b c Schmadel, Lutz D. (2007). "(4902) Thessandrus". Dictionary of Minor Planet Names . Springer Berlin Heidelberg . p. 423. doi :10.1007/978-3-540-29925-7_4792 . ISBN 978-3-540-00238-3 ^ a b c d "JPL Small-Body Database Browser: 4902 Thessandrus (1989 AN2)" (2018-05-20 last obs.). Jet Propulsion Laboratory . Retrieved 17 June 2018 .^ a b "List of Jupiter Trojans" . Minor Planet Center . 1 June 2018. Retrieved 17 June 2018 .^ a b "Asteroid (4902) Thessandrus – Proper Elements" . AstDyS-2, Asteroids – Dynamic Site. Retrieved 17 June 2018 .^ a b c d Grav, T.; Mainzer, A. K.; Bauer, J. M.; Masiero, J. R.; Nugent, C. R. (November 2012). "WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy" . The Astrophysical Journal . 759 (1): 10. arXiv :1209.1549 Bibcode :2012ApJ...759...49G . doi :10.1088/0004-637X/759/1/49 . S2CID 119101711 . Retrieved 17 June 2018 . online catalog )^ a b c d e f g "LCDB Data for (4902) Thessandrus" . Asteroid Lightcurve Database (LCDB). Retrieved 30 June 2016 .^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey" . Publications of the Astronomical Society of Japan . 63 (5): 1117– 1138. Bibcode :2011PASJ...63.1117U . doi :10.1093/pasj/63.5.1117 online , AcuA catalog p. 153 )^ a b c French, Linda M.; Stephens, Robert, D.; Coley, Daniel R.; Wasserman, Lawrence H.; Vilas, Faith; La Rocca, Daniel (October 2013). "A Troop of Trojans: Photometry of 24 Jovian Trojan Asteroids" . The Minor Planet Bulletin . 40 (4): 198– 203. Bibcode :2013MPBu...40..198F . ISSN 1052-8091 . Retrieved 30 June 2016 . {{cite journal }}: CS1 maint: multiple names: authors list (link )^ a b Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus . 261 : 34– 47. arXiv :1506.00762 Bibcode :2015Icar..261...34V . doi :10.1016/j.icarus.2015.08.007 . S2CID 53493339 . ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids" . Astronomy and Astrophysics . 510 : 12. Bibcode :2010A&A...510A..43C . doi :10.1051/0004-6361/200913322 . Retrieved 30 October 2019 . (PDS data set) ^ "MPC/MPO/MPS Archive" . Minor Planet Center . Retrieved 17 June 2018 .
External links
