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 8 February 1889
Designations
Main belt (Eos)
Orbital characteristics[2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc 122.26 yr (44655 d)
Aphelion 3.49701 AU (523.145 Gm)
Perihelion 2.59675 AU (388.468 Gm)
3.04688 AU (455.807 Gm)
Eccentricity 0.14773
5.32 yr (1942.6 d)
17.07 km/s
127.107°
0° 11m 7.148s / day
Inclination 7.99162°
304.369°
53.7020°
Known satellites 1 (9±5 km)[1]
Earth MOID 1.601 AU (239.5 Gm)
Jupiter MOID 1.97626 AU (295.644 Gm)
Jupiter Tisserand parameter 3.207
Physical characteristics
Dimensions 148.06±4.6 km (IRAS)[2]
160±10 km (AO)[1]
Mass 1.38×1018 kg[3]
Mean density
0.81±0.08 g/cm³[3]
Equatorial surface gravity
unknown
Equatorial escape velocity
unknown
6.896 h (0.2873 d)[2]
0.0262±0.002[2] (Dark)
Temperature unknown
unknown
8.72[2]

283 Emma is a large asteroid of the asteroid belt. 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:0804.1385free to read. Bibcode:2008Icar..195..295M. doi:10.1016/j.icarus.2007.12.010. 
  2. ^ a b c d e "JPL Small-Body Database Browser: 283 Emma" (2008-10-30 last obs). Retrieved 11 May 2016. 
  3. ^ a b Jim Baer (2010-12-12). "Recent Asteroid Mass Determinations". Personal Website. Retrieved 2015-07-17. 
  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:1204.1116free to read, Bibcode:2012arXiv1204.1116R. 
  6. ^ S/2003 (283) 1 (Circular No. 8165)

External links[edit]