Sources
Help build the largest human-edited directory on the web.
Submit a site - Become an editor
Wikipedia. Licensed under the GNU Free Documentation License.
Are you an expert in this subject? Join the discussion and share your knowledge at Wikipedia.org.
140 Siwa
From Wikipedia, the free encyclopedia
| Discovery | |
|---|---|
| Discovered by: | Johann Palisa |
| Discovery date: | October 13, 1874 |
| Alternative names: | |
| Minor planet category: | Main belt |
| Orbital characteristics | |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion distance: | 497.275 Gm (3.324 AU) |
| Perihelion distance: | 320.360 Gm (2.141 AU) |
| Semi-major axis: | 408.817 Gm (2.733 AU) |
| Eccentricity: | 0.216 |
| Orbital period: | 1650.076 d (4.52 a) |
| Avg. orbital speed: | 17.80 km/s |
| Mean anomaly: | 156.165° |
| Inclination: | 3.187° |
| Longitude of ascending node: | 107.292° |
| Argument of perihelion: | 197.230° |
| Physical characteristics | |
| Dimensions: | 109.8 km |
| Mass: | 1.4×1018 kg |
| Mean density: | ? g/cm³ |
| Equatorial surface gravity: | 0.0307 m/s² |
| Escape velocity: | 0.0580 km/s |
| Rotation period: | ? d |
| Albedo: | ? |
| Temperature: | ~168 K |
| Spectral type: | ? |
| Absolute magnitude: | 8.34 |
140 Siwa is a large and dark main belt asteroid. It has a composition of a P (or possibly C-type) asteroid. It was discovered by J. Palisa on October 13, 1874 and named after Siwa, the Slavic goddess of fertility. Siwa has a very flat lightcurve, indicating a spherical body.
The Rosetta comet probe was to visit Siwa on its way to comet 46P/Wirtanen in July, 2008. However, the mission was rerouted to comet 67P/Churyumov-Gerasimenko and the flyby had to be abandoned.
| Minor planets | ||
|---|---|---|
| Previous minor planet | 140 Siwa | Next minor planet |
| List of asteroids | ||
Vulcanoids · Near-Earth asteroids · Main belt · Jupiter Trojans · Centaurs · Damocloids · Comets · Trans-Neptunians (Kuiper belt • Scattered disc • Oort cloud)
For other objects and regions, see Asteroid groups and families, Binary asteroids, Asteroid moons and the Solar System.
For a complete listing, see List of asteroids. See also Pronunciation of asteroid names and Meanings of asteroid names.