S / 2003 (283) 1
(283) Emma I (S / 2002 (121) 1) 1) | |
---|---|
Provisional or systematic name | S / 2003 (283) 1 |
Central body | (283) Emma |
Properties of the orbit | |
Major semi-axis | 581 ± 3.6 km |
Periapsis | 511 km |
Apoapsis | 651 km |
eccentricity | 0.12 ± 0.01 |
Orbit inclination | 94.2 ± 0.4 ° |
Orbital time | 3.353 ± 0.00093 d |
Physical Properties | |
Albedo | ≈ 0.032 ± 0.004 |
Medium diameter | 9.0 ± 5.0 km |
surface | 255 km 2 |
Surface temperature | 184 K |
discovery | |
Explorer |
|
Date of discovery | July 14, 2003 |
Remarks | Largest moon in the asteroid belt |
S / 2003 (283) 1 is a moon of the main belt asteroid (283) Emma . Its mean diameter is 9 kilometers.
Discovery and naming
S / 2003 (283) 1 was published on July 14, 2003 by William J. Merline, Christophe Dumas, Laird M. Close, Clark R. Chapman, Peter M. Tamblyn, D. Terrell, AR Conrad, François Menard and Gilles Duvert Use of adaptive optics discovered with the 10 m Keck Telescope II on Mauna Kea in Hawaii . The discovery was announced on July 27, 2003; the moon was given the provisional designation S / 2003 (283) 1 . An official naming by the IAU is still pending.
Track properties
S / 2003 (283) 1 orbits Emma on a retrograde , slightly elliptical orbit at an average distance of 581 kilometers from the center (about 4.4 Emma radii). The orbital eccentricity is 0.12, the orbit is 94.2 ° inclined to the equator of Emma .
S / 2003 (283) 1 orbits Emma in 3 days, 8 hours and 28 minutes, which corresponds to about 581 orbits in an Emma year (around 5.3 earth years). The orbit of S / 2003 (283) 1 is assumed to be stable because it is well within Emma's Hill radius of 24,000 km, but also well outside of the synchronous orbit.
Physical Properties
size
According to current data, S / 2003 (283) 1 has a diameter of 9 km (almost 1/15 of the central body), based on Emma's density and the corresponding assumed equal reflectivity of only 3.2%. The surface is therefore extremely dark. On the basis of the data so far, however, the determination of the diameter still seems relatively uncertain; it currently ranges from 4 to 14 km.
Assuming a mean diameter of 9 km, the surface area is around 254.5 km 2 , which is slightly larger than the area of the Swiss canton of Appenzell Ausserrhoden .
Determination of the diameter for S / 2003 (283) 1
year | Dimensions km | source |
---|---|---|
2003 | 12.0 | IAU |
2008 | 9.0 ± 5.0 | Marchis et al. |
2016 | 10.0 | Vachier et al. |
The most precise determination is marked in bold .
internal structure
Since S / 2003 (283) 1 has a similar color to the mother body, it is assumed that the moon is made of the same material as Emma and therefore has the same spectral type (X or P).
The mean surface temperature is 184 K (−89 ° C).
See also
Web links
Individual evidence
- ^ A b Daniel WE Green: IAUC No. 8165: S / 2003 (283) 1 discovery publication (July 2003). Retrieved September 12, 2017 .
- ^ Franck Marchis et al .: Main belt binary asteroidal systems with eccentric mutual orbits (May 2008) (PDF). Retrieved September 12, 2017 .
- ↑ Frédéric Vachier: Sunday 20th of November 2016 ~ 18:40:12 UTC (283) Emma occult 4U 455-51223 (mag 8.7) (November 2016). Retrieved September 12, 2017 .