113 Amalthea

113 Amalthea
Discovery
Discovered by	R. Luther
Discovery site	Bilk Obs.
Discovery date	12 March 1871
Designations
MPC designation	(113) Amalthea
Pronunciation	/æməlˈθiːə/[1]
Named after	Amalthea
Minor planet category	main-belt · Flora
Orbital characteristics[2]
	Epoch 31 July 2016 (JD 2457600.5)
	Uncertainty parameter 0
Observation arc	144.90 yr (52926 d)
Aphelion	2.5819 AU (386.25 Gm)
Perihelion	2.17010 AU (324.642 Gm)
Semi-major axis	2.37598 AU (355.442 Gm)
Eccentricity	0.086651
Orbital period	3.66 yr (1337.7 d)
Mean anomaly	226.48°
Mean motion	0° 16m 8.832s / day
Inclination	5.0422°
Longitude of ascending node	123.486°
Argument of perihelion	79.118°
Known satellites	1[3]
Physical characteristics
Mean diameter	46.14±1.4 km
Rotation period	9.950 h (0.4146 d)
Geometric albedo	0.2649±0.017
Spectral type	S
Absolute magnitude (H)	8.74

113 Amalthea /æməlˈθiːə/ is a stony Florian asteroid and binary system from the inner regions of the asteroid belt, approximately 50 kilometers (31 miles) in diameter. It was discovered on 12 March 1871, by German astronomer Robert Luther at the Bilk Observatory in Düsseldorf, Germany. The elongated S-type asteroid has a rotation period of 9.95 hours. It was named after Amalthea from Greek mythology. The discovery of its 5-kilometer satellite was announced in July 2017.

Description

Amalthea is thought to be a fragment from the mantle of a Vesta-sized, 300–600 km diameter parent body that broke up around one billion years ago, with the other major remnant being 9 Metis.[4] The spectrum of Amalthea reveals the presence of the mineral olivine, a relative rarity in the asteroid belt.[5][6]

Based on observations made during a stellar occultation by Amalthea of a 10th-magnitude star on 14 March 2017, it was announced in July 2017 that the asteroid has a small, 5-kilometer-sized satellite, provisionally designated S/2017 (113) 1. The observations also indicated that Amalthea has a distinctly elongated shape.[3]

One of Jupiter's inner small satellites, unrelated to 113 Amalthea, is also called Amalthea.

References

'Amalthaea' in Noah Webster (1884) A Practical Dictionary of the English Language
Yeomans, Donald K., "113 Amalthea", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 12 May 2016.
Beatty, Kelly. "Amateur Observers Find an Asteroid's Moon". Sky & Telescope. Retrieved 15 July 2017.
Kelley, Michael S.; Gaffey, Michael J. (March 2000), "9 Metis and 113 Amalthea: A Genetic Asteroid Pair", Icarus, 35 (144), pp. 27–38, Bibcode:2000Icar..144...27K, doi:10.1006/icar.1999.6266.
Cloutis, E. A. (March 1993), "Olivine-rich asteroids, pallasitic olivine and olivine-metal mixtures: Comparisons of reflectance spectra", Lunar and Planetary Institute, Twenty-fourth Lunar and Planetary Science Conference. Part 1: A-F, pp. 317–318, Bibcode:1993LPI....24..317C.
Burbine, T. H.; et al. (July 2000), "The Nature of Olivine Asteroids", Meteoritics & Planetary Science, 35, pp. A35, Bibcode:2000M&PSA..35R..35B, doi:10.1111/j.1945-5100.2000.tb01796.x.

External links

(113) Amalthea and S/2017 (113) 1, Asteroids with Satellites Database, Johnston's Archive
113 Amalthea at AstDyS-2, Asteroids—Dynamic Site
- Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
113 Amalthea at the JPL Small-Body Database
- Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[1] 'Amalthaea' in Noah Webster (1884) A Practical Dictionary of the English Language

[JPL-2] Yeomans, Donald K., "113 Amalthea", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 12 May 2016.

[SkyTel-3] Beatty, Kelly. "Amateur Observers Find an Asteroid's Moon". Sky & Telescope. Retrieved 15 July 2017.

[Kelley2000-4] Kelley, Michael S.; Gaffey, Michael J. (March 2000), "9 Metis and 113 Amalthea: A Genetic Asteroid Pair", Icarus, 35 (144), pp. 27–38, Bibcode:2000Icar..144...27K, doi:10.1006/icar.1999.6266.

[Cloutis1993-5] Cloutis, E. A. (March 1993), "Olivine-rich asteroids, pallasitic olivine and olivine-metal mixtures: Comparisons of reflectance spectra", Lunar and Planetary Institute, Twenty-fourth Lunar and Planetary Science Conference. Part 1: A-F, pp. 317–318, Bibcode:1993LPI....24..317C.

[Burbine2000-6] Burbine, T. H.; et al. (July 2000), "The Nature of Olivine Asteroids", Meteoritics & Planetary Science, 35, pp. A35, Bibcode:2000M&PSA..35R..35B, doi:10.1111/j.1945-5100.2000.tb01796.x.