Iapetus (moon)
Iapetus (/aɪˈæpətəs/) is a moon of Saturn. With an estimated diameter of 1,469 km, it is the third-largest moon of Saturn and the eleventh-largest in the Solar System. Named after the Titan Iapetus, the moon was discovered in 1671 by Giovanni Domenico Cassini.
A Cassini mosaic image of Iapetus | |
| Discovery | |
|---|---|
| Discovered by | G. D. Cassini |
| Discovery date | October 25, 1671 |
| Designations | |
Designation | Saturn VIII |
| Pronunciation | /aɪˈæpətəs/ |
Named after | Ἰαπετός Īapetus |
| Adjectives | Iapetian /aɪəˈpiːʃən/ |
| Orbital characteristics | |
| 3560820 km | |
| Eccentricity | 0.0276812 |
| 79.3215 d | |
Average orbital speed | 3.26 km/s |
| Inclination |
|
| Satellite of | Saturn |
| Physical characteristics | |
| Dimensions | 1,492.0 × 1,492.0 × 1,424 km |
Mean radius | 734.4±2.8 km |
| 6700000 km2 | |
| Mass | (1.8056591±0.0000544)×1021 kg |
Mean density | 1.0887±0.0127 g/cm3 |
| 0.223 m/s2 (0.0228 g) (0.138 Moons) | |
| 0.573 km/s | |
| 79.3215 d (synchronous) | |
| zero | |
| Albedo | 0.05–0.5 |
| Temperature | 90–130 K |
| 10.2–11.9 | |
A relatively low-density body made up mostly of ice, Iapetus is home to several distinctive and unusual features, such as a striking difference in coloration between its leading hemisphere, which is dark, and its trailing hemisphere, which is bright, as well as a massive equatorial ridge running three-quarters of the way around the moon.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.