1208 Troilus

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1208 Troilus
Discovery [1]
Discovered by K. Reinmuth
Discovery site Heidelberg Obs.
Discovery date 31 December 1931
Designations
MPC designation (1208) Troilus
Pronunciation /ˈtrɔɪləs/ TROY-ləs
Named after
Troilus (Greek mythology)[2]
1931 YA · 1965 WK
Jupiter trojan[3]
(Trojan camp)[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 85.50 yr (31,229 days)
Aphelion|Aphelion 5.7305 AU
Perihelion|Perihelion 4.7701 AU
5.2503 AU
Eccentricity 0.0915
12.03 yr (4,394 days)
172.55°
0° 4m 54.84s / day
Inclination 33.542°
48.547°
296.25°
Jupiter MOID 0.0025 AU
Jupiter Tisserand parameter 2.6590
Physical characteristics
Dimensions 100.477±1.097[5]
100.48±1.10 km[6]
103.31 km (derived)[3]
103.34 km[7]
111.36±2.36 km[8]
24 h[9]
56.17±0.07 h[1][10]
63.8±0.5 h[11]
0.037±0.002[8]
0.0397 (derived)[3]
0.041±0.006[6][5]
0.0419±0.003[1]
Tholen = FCU [1] · F[3]
B–V = 0.693±0.033[1]
B–V =0.750±0.050[12]
U–B = 0.314±0.093[1]
V–R = 0.380±0.030[12]
V–I = 0.720±0.013[12]
8.99[1][7][8] · 9.05[3][9] · 9.08[6][13]

1208 Troilus (/ˈtrɔɪləs/ TROY-ləs ), provisional designation 1931 YA, is a highly inclined Jupiter trojan, approximately 103 kilometers in diameter. It was discovered on 31 December 1931, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany.[14] It was named after Troilus from Greek mythology.

Orbit and classification[edit]

Troilus is located in the L5 Lagrangian point, 60° behind Jupiter in the so-called Trojan camp.[4] It orbits the Sun at a distance of 4.8–5.7 AU once every 12.03 years (4,394 days). Its orbit has an eccentricity of 0.09 and an inclination of 34° with respect to the ecliptic.[1] The body's observation arc begins with its official discovery observation.[14]

Physical characteristics[edit]

The carbonaceous asteroid has a relatively rare F-type spectrum, characterized as a FCU-type in the Tholen taxonomic system. Troilus has a rotation period of 56 hours[10] with a more recent but provisional 2014-measurement of 63 hours.[11] The body's albedo amounts to 0.04, according to the surveys carried out by the space-spaced missions, IRAS, Akari, and WISE/NEOWISE.[7][8][6]

Naming[edit]

This minor planet was named after the young Trojan prince Troilus from Greek mythology. He is 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).[2]

References[edit]

  1. ^ a b c d e f g h i "JPL Small-Body Database Browser: 1208 Troilus (1931 YA)" (2017-07-01 last obs.). Jet Propulsion Laboratory. Retrieved 3 August 2017. 
  2. ^ a b Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1208) Troilus. Springer Berlin Heidelberg. p. 101. ISBN 978-3-540-00238-3. Retrieved 3 August 2017. 
  3. ^ a b c d e "LCDB Data for (1208) Troilus". Asteroid Lightcurve Database (LCDB). Retrieved 3 August 2017. 
  4. ^ a b "List of Jupiter Trojans". Minor Planet Center. 20 August 2016. Retrieved 12 December 2016. 
  5. ^ a b 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:1209.1549Freely accessible. Bibcode:2012ApJ...759...49G. doi:10.1088/0004-637X/759/1/49. Retrieved 3 August 2017. 
  6. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 22 November 2015. 
  7. ^ a b c Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. Bibcode:2004PDSS...12.....T. Retrieved 22 November 2015. 
  8. ^ 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. Retrieved 3 August 2017. 
  9. ^ a b French, L. M. (November 1987). "Rotation properties of four L5 Trojan asteroids from CCD photometry". Icarus: 325–341.MIT–supportedresearch. Bibcode:1987Icar...72..325F. doi:10.1016/0019-1035(87)90178-3. ISSN 0019-1035. Retrieved 22 November 2015. 
  10. ^ a b Molnar, Lawrence A.; Haegert, Melissa J.; Hoogeboom, Kathleen M. (June 2008). "Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids". The Minor Planet Bulletin. 35 (2): 82–84. Bibcode:2008MPBu...35...82M. ISSN 1052-8091. Retrieved 22 November 2015. 
  11. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1208) Troilus". Geneva Observatory. Retrieved 3 August 2017. 
  12. ^ a b c Chatelain, Joseph P.; Henry, Todd J.; French, Linda M.; Winters, Jennifer G.; Trilling, David E. (June 2016). "Photometric colors of the brightest members of the Jupiter L5 Trojan cloud". Icarus. 271: 158–169. Bibcode:2016Icar..271..158C. doi:10.1016/j.icarus.2016.01.026. Retrieved 4 August 2017. 
  13. ^ Schaefer, Martha W.; Schaefer, Bradley E.; Rabinowitz, David L.; Tourtellotte, Suzanne W. (June 2010). "Phase curves of nine Trojan asteroids over a wide range of phase angles". Icarus. 207 (2): 699–713. arXiv:0912.1888Freely accessible. Bibcode:2010Icar..207..699S. doi:10.1016/j.icarus.2009.11.031. Retrieved 3 August 2017. 
  14. ^ a b "1208 Troilus (1931 YA)". Minor Planet Center. Retrieved 3 August 2017. 

External links[edit]