283 Emma
.png)
A three-dimensional model of 283 Emma based on its light curve.
|
|
| Discovery | |
|---|---|
| Discovered by | Auguste Charlois |
| Discovery date | February 8, 1889 |
| Designations | |
| 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) | |
|
Average orbital speed
|
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 | 1.38×1018 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 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
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
- ↑ 1.0 1.1 1.2 1.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 2.2 2.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 3.0 3.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lutz D. Schmadel, Dictionary of Minor Planet Names, 5th edtn. (2003), Appendix 11, p.40.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ S/2003 (283) 1 (Circular No. 8165)
External links
- Orbital simulation from JPL (Java) / Ephemeris
- Orbits of Binary Asteroids with Adaptive Optics (VLT images)
