|
Discovery
|
|
|---|---|
| Discovered by | James Craig Watson |
| Discovery date | October 10, 1874 |
|
Designations
|
|
| Alternate name(s) | |
| Minor planet category |
Main belt |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 488.346 Gm (3.264 AU) |
| Perihelion | 344.626 Gm (2.304 AU) |
| Semi-major axis | 416.486 Gm (2.784 AU) |
| Eccentricity | 0.173 |
| Orbital period | 1696.721 d (4.65 a) |
| Average orbital speed | 17.72 km/s |
| Mean anomaly | 35.886° |
| Inclination | 10.902° |
| Longitude of ascending node | 2.014° |
| Argument of perihelion | 166.350° |
|
Physical characteristics
|
|
| Dimensions | 156.6 km |
| Mass | 4.0×1018 kg |
| Mean density | ? g/cm³ |
| Equatorial surface gravity | 0.0438 m/s² |
| Escape velocity | 0.0828 km/s |
| Rotation period | ? d |
| Albedo | ? |
| Temperature | ~167 K |
| Spectral type | CP |
| Absolute magnitude (H) | 7.78 |
139 Juewa ( /dʒuːˈeɪwɑː/ jew-ay-wah) is a very large and dark main belt asteroid. It is probably composed of primitive carbonaceous material. It was the first asteroid discovered from China.
Juewa was discovered from Beijing by the visiting American astronomer James Craig Watson on October 10, 1874; Watson was in China to observe the transit of Venus. Watson asked Prince Gong to name the asteroid. Gong's choice was 華星 (roughly, "Star of China’s Fortune"). Watson used only the first character, transliterating it as Juewa according to the conventions of his time (in modern pinyin, it would be transliterated as ruìhuá).[1]
There have been three reported stellar occultations by Juewa.
|
|||||
|
||||||||||||||||||||||