283 Emma

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283 Emma
283Emma (Lightcurve Inversion).png
A three-dimensional model of 283 Emma based on its light curve.
Discovery
Discovered by Auguste Charlois
Discovery date February 8, 1889
Designations
Minor planet category Main belt (Eos)
Orbital characteristics
Epoch 30 January 2005 (JD 2453400.5)
Aphelion 524.763 Gm (3.508 AU)
Perihelion 385.674 Gm (2.578 AU)
455.219 Gm (3.043 AU)
Eccentricity 0.153
1938.796 d (5.31 a)
17.07 km/s
67.855°
Inclination 7.991°
304.506°
54.031°
Known satellites 1 (9±5 km)[1]
Physical characteristics
Dimensions 148±5 km (IRAS)[2]
160±10 km (AO)[1]
Mass 1.3×1018 kg[3]
Mean density
0.81±0.08 g/cm³[3]
unknown
unknown
6.888 h[2]
Albedo 0.0262[2] (Dark)
Temperature unknown
Spectral type
unknown
8.72[2]

283 Emma is a large main-belt asteroid. It was discovered by Auguste Charlois on February 8, 1889, in Nice, France. The reason for its name is unknown.[4]

Measurements made with the IRAS observatory give a diameter of 145.70 ± 5.89 km and a geometric albedo of 0.03 ± 0.01. By comparison, the MIPS photometer on the Spitzer Space Telescope gives a diameter of 145.44 ± 7.72 km and a geometric albedo of 0.03 ± 0.01. When the asteroid was observed occulting a star, the results showed a diameter of 148.00 ± 16.26 km.[5]

Satellite[edit]

A companion for 283 Emma was detected on 14 July 2003 by W. J. Merline et al. using the Keck II telescope and is designated S/2003 (283) 1. The announcement is contained in the International Astronomical Union Circular (IAUC) 8165.[6] The satellite orbits at a semi-major axis of about 581 km with an eccenticity of 0.12.[1] Emma has a hill sphere with a radius of about 28,000 km.[1]

References[edit]

  1. ^ a b c d Marchis, Franck; P. Descamps, J. Berthier, D. hestroffer, F. vachier, M. Baek, A. Harris, D. Nesvorny (2008). "Main Belt Binary Asteroidal Systems With Eccentric Mutual Orbits". Icarus 195 (1): 295–316. arXiv:0804.1385. Bibcode:2008Icar..195..295M. doi:10.1016/j.icarus.2007.12.010. 
  2. ^ a b c d "JPL Small-Body Database Browser: 283 Emma". 2008-10-30 last obs. Retrieved 2008-11-27. 
  3. ^ a b Jim Baer (2008). "Recent Asteroid Mass Determinations". Personal Website. Retrieved 2008-11-27. 
  4. ^ Lutz D. Schmadel, Dictionary of Minor Planet Names, 5th edtn. (2003), Appendix 11, p.40.
  5. ^ Ryan, Erin Lee et al. (April 2012), "The Kilometer-Sized Main Belt Asteroid Population as Revealed by Spitzer", eprint arXiv, arXiv:1204.1116, Bibcode:2012arXiv1204.1116R. 
  6. ^ S/2003 (283) 1 (Circular No. 8165)

External links[edit]