624 Hektor
![]() Star field showing Hektor (apmag 15) | |
Discovery | |
---|---|
Discovered by | August Kopff |
Discovery date | 10 February 1907 |
Designations | |
Named after | Hector |
1907 XM; 1948 VD | |
Trojan asteroid | |
Adjectives | Hektorian |
Orbital characteristics[1] | |
Epoch 22 October 2004 (JD 2453300.5) | |
Aphelion | 5.349 AU (800.220 Gm) |
Perihelion | 5.095 AU (762.145 Gm) |
5.222 AU (781.183 Gm) | |
Eccentricity | 0.024 |
11.93 a (4358.521 d) | |
Average orbital speed | 13.03 km/s |
94.752° | |
Inclination | 18.198° |
342.791° | |
183.579° | |
Known satellites | S/2006 (624) 1[2] (15km diameter) |
Physical characteristics | |
Dimensions | 370 km × 195 km × 195 km[3] |
Mass | ~1.4×1019 kg |
Mean density | 2.1 ± 0.3 g/cm³ |
~0.067 m/s² | |
~0.13 km/s | |
0.2884 d (6.92 h)[4] | |
Albedo | 0.025 (geometric)[1] |
Temperature | ~122 K |
Spectral type | D |
13.79 to 15.26 | |
7.49[1] | |
0.078" to 0.048" | |
624 Hektor (/[invalid input: 'icon']ˈhɛktɔːr/ HEK-tor) is the largest Jupiter Trojan. It was discovered in 1907 by August Kopff.
Hektor is a D-type asteroid, dark and reddish in colour. It lies in Jupiter's leading Lagrangian point, L4, called the 'Greek' node after one of the two sides in the legendary Trojan War. Hektor is named after the Trojan hero Hektor and is thus one of two trojan asteroids that is "misplaced" in the wrong camp (the other being 617 Patroclus in the Trojan node).
Contact binary plus moonlet
Hektor is one of the most elongated bodies of its size in the Solar System, being 370 × 200 km. It is thought that Hektor might be a contact binary (two asteroids joined by gravitational attraction) like 216 Kleopatra. Hubble Space Telescope observations of Hektor in 1993 did not show an obvious bilobate shape[citation needed] because of a limited angular resolution. On 17 July 2006, the Keck-10m II telescope and its Laser guide star Adaptive Optics (AO) system indicated a bilobate shape for Hektor[citation needed]. Additionally, a 15-km moonlet at 1000 km of Hektor was detected. The satellite's provisional designation is S/2006 (624) 1.[2] Hektor is, so far, the only known binary trojan asteroid in the L4 point and the first trojan with a satellite companion. 617 Patroclus, another large trojan asteroid located in the L5, is composed of two same-sized components.
Hektor in fiction
- See Asteroids in fiction.
References
- ^ a b c "JPL Small-Body Database Browser: 624 Hektor (1907 XM)". 5 September 2008 last obs. Retrieved 1 November 2008.
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(help) - ^ a b "IAUC 8732: S/2006 (624) 1 (Satellite Discovery)". Retrieved 23 July 2006.
- ^ Storrs, Alex; Weiss, B.; Zellner, B.; et al. (1998). "Imaging Observations of Asteroids with Hubble Space Telescope" (PDF). Icarus. 137 (2): 260–268. Bibcode:1999Icar..137..260S. doi:10.1006/icar.1999.6047. Retrieved 22 May 2008.
- ^ Detal, A.; Hainaut, O.; Pospieszalska-Surdej, A.; Schils, P.; Schober, H. J.; Surdej, J. (1994). "Pole, albedo and shape of the minor planets 624 Hektor and 43 Ariadne". Astronomy and Astrophysics (ISSN 0004-6361). 281: 269. Bibcode:1994A&A...281..269D.
External links
- Orbital simulation from JPL (Java) / Ephemeris
- Keck image of Hektor and moon (Marchis 2011-Nov-11)