Saturn IX
E257499
Saturn IX, officially named Phoebe, is an irregular, retrograde outer moon of Saturn believed to be a captured object from the outer Solar System.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Saturn IX canonical | 2 |
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
irregular satellite
ⓘ
natural satellite ⓘ outer moon of Saturn ⓘ retrograde satellite ⓘ |
| albedo | low ⓘ |
| alternativeName | S/1899 S 1 ⓘ |
| belongsTo | Solar System ⓘ |
| belongsToGroup | Norse group of Saturnian moons ⓘ |
| belongsToPlanetarySystem | Saturnian system ⓘ |
| catalogDesignation | Saturn IX self-link ⓘ |
| density | approximately 1.6 g/cm³ ⓘ |
| diameter | approximately 213 km ⓘ |
| discoveredBy | William Henry Pickering ⓘ |
| discoveryMethod | ground-based telescope observations ⓘ |
| discoveryYear | 1899 ⓘ |
| eccentricity | approximately 0.163 ⓘ |
| equatorialSurfaceGravity | about 0.05 m/s² ⓘ |
| escapeVelocity | about 0.1 km/s ⓘ |
| firstCloseImagingBy | Cassini–Huygens ⓘ |
| firstCloseImagingYear | 2004 ⓘ |
| geometricAlbedo | about 0.06 ⓘ |
| hasNo |
known geological activity
ⓘ
substantial atmosphere ⓘ |
| hasSpacecraftFlyby | Cassini–Huygens ⓘ |
| inclination | about 175 degrees to the ecliptic ⓘ |
| likelyOrigin | captured object from the outer Solar System ⓘ |
| mass | approximately 8.3×10^18 kg ⓘ |
| meanRadius | approximately 106.5 km ⓘ |
| meanSurfaceTemperature | very low (tens of kelvin) ⓘ |
| namedAfter | Phoebe (figure in Greek mythology) ⓘ |
| officialName | Phoebe ⓘ |
| orbitalClass | irregular ⓘ |
| orbitalDirection | retrograde ⓘ |
| orbitalPeriod | approximately 550 Earth days ⓘ |
| orbits | Saturn ⓘ |
| possibleType | captured centaur or Kuiper belt object ⓘ |
| roleInSystem | source of dark material for Iapetus (hypothesized) ⓘ |
| rotationPeriod | approximately 9.27 hours ⓘ |
| rotationState | not tidally locked to Saturn ⓘ |
| semiMajorAxis | approximately 12.95 million km from Saturn ⓘ |
| shape | roughly spherical but irregular ⓘ |
| spectralType | C-type or D-type like ⓘ |
| surfaceColor | very dark ⓘ |
| surfaceComposition | water ice and dark carbon-rich material ⓘ |
| surfaceFeatures |
covered with dark material
ⓘ
heavily cratered ⓘ large impact basins ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.