1868 Thersites

1868 Thersites
Discovery [1]
Discovered by C. J. van Houten
I. van Houten
T. Gehrels
Discovery site Palomar Obs.
Discovery date 24 September 1960
Designations
MPC designation 1868 Thersites
Named after
 Thersites
(Greek mythology)[2]
2008 P-L · 1972 RB2
Jupiter trojan [3][4]
(Greek camp)
Orbital characteristics [1]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc 61.95 yr (22,629 days)
Aphelion 5.8983 AU
Perihelion 4.7419 AU
5.3201 AU
Eccentricity 0.1086
12.27 yr (4,482 days)
213.14°
0° 4m 49.08s / day
Inclination 16.753°
197.84°
169.69°
Jupiter MOID 0.2004 AU
Jupiter Tisserand parameter 2.903
Physical characteristics
Dimensions 78.89±2.02 km[5]
68.16±0.81 km[6]
66.92 km (calculated)[3]
10.416±0.014 h[7]
0.055±0.003[5]
0.055±0.008[6]
0.057 (assumed)[3]
C [3]
9.6[1][3][6]
9.30[5]

    1868 Thersites, provisional designation 2008 P-L, is a carbonaceous Jupiter trojan from the Greek camp, approximately 70 kilometers in diameter. It was discovered by Dutch astronomer couple Ingrid and Cornelis van Houten at Leiden, on photographic plates taken by Dutch-American astronomer Tom Gehrels at the U.S. Palomar Observatory, California, on 24 September 1960.[4] On the same day, the group discovered another Jupiter trojan, 1869 Philoctetes.

    The dark C-type asteroid is orbiting in the leading Greek camp at Jupiter's L4 Lagrangian point, 60° ahead of its orbit (see Trojans in astronomy). It orbits the Sun at a distance of 4.7–5.9 AU once every 12.27 years (4,482 days). Its orbit has an eccentricity of 0.11 and an inclination of 17° with respect to the plane of the ecliptic.[1] A precovery of this asteroid was already obtained at Palomar Observatory in 1954.[4]

    In 1994, photometric observations of this asteroid were made by Stefano Mottola at ESO's La Silla Observatory, Chile, using the Dutch 0.9-metre Telescope. The observations were used to build a light-curve showing a rotation period of 10.416±0.014 hours with a brightness variation of 0.14±0.01 magnitude (U=2+).[7] According to the space-based surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid's diameter measures 78.9 and 68.2 kilometers, respectively, with a low albedo of 0.055 for its surface.[5][6] The Collaborative Asteroid Lightcurve Link (CALL) assumes a slightly higher albedo of 0.057 and calculates a shorter diameter of 66.92 kilometers.[3]

    The provisional survey designation "P-L" stands for Palomar–Leiden, named after Palomar Observatory and Leiden Observatory, which collaborated on the fruitful Palomar–Leiden survey in the 1960s and 1970s. Gehrels used Palomar's Samuel Oschin telescope (also known as the 48-inch Schmidt Telescope), and shipped the photographic plates to Cornelis and Ingrid van Houten at Leiden Observatory, where astrometry was carried out. The trio are credited with the discovery of 4,619 minor planets.[8]

    The Trojan asteroid is named after Thersites, a Greek warrior who wanted to abandon Troy's siege during the Trojan War and head home. The given name also refers to the fact, that the asteroid was discovered farthest from the L4 Lagrangian point.[2]

    References

    1. 1 2 3 4 "JPL Small-Body Database Browser: 1868 Thersites (2008 P-L)" (2016-03-11 last obs.). Jet Propulsion Laboratory. Retrieved March 2016.
    2. 1 2 Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1868) Thersites. Springer Berlin Heidelberg. p. 150. ISBN 978-3-540-00238-3. Retrieved March 2016.
    3. 1 2 3 4 5 6 "LCDB Data for (1868) Thersites". Asteroid Lightcurve Database (LCDB). Retrieved March 2016.
    4. 1 2 3 "1868 Thersites (2008 P-L)". Minor Planet Center. Retrieved March 2016.
    5. 1 2 3 4 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 March 2016.
    6. 1 2 3 4 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:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved March 2016.
    7. 1 2 Mottola, Stefano; Di Martino, Mario; Erikson, Anders; Gonano-Beurer, Maria; Carbognani, Albino; Carsenty, Uri; et al. (May 2011). "Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects". The Astronomical Journal 141 (5): 32. Bibcode:2011AJ....141..170M. doi:10.1088/0004-6256/141/5/170. Retrieved March 2016.
    8. ↑ "Minor Planet Discoverers". Minor Planet Center. 23 March 2016. Retrieved March 2016.

    External links


    This article is issued from Wikipedia - version of the Thursday, April 21, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.