Links
- Wikipedia
- Phoebe on Wikipedia
Phoebe
Details
Phoebe is a dark irregular moon of Saturn with a distant, retrograde orbit. Cassini's 2004 flyby showed a battered icy-rocky body that may be a captured outer Solar System object, making Phoebe a clue to material beyond Saturn's regular moons.
Phoebe matters because it does not behave like a moon that grew quietly in Saturn's regular satellite system. Its orbit is distant, inclined, and retrograde, moving opposite the direction of most major Saturnian moons. That orbital oddness makes Phoebe feel less like a normal family member and more like an object Saturn captured from elsewhere.
Cassini made that story physical. The 2004 flyby revealed a small, dark, heavily cratered world whose surface and orbit point toward an origin in the outer Solar System. NASA describes Phoebe as a possible captured Centaur, a kind of primitive body associated with material that migrated inward from the Kuiper Belt region.
That is why Phoebe matters on this scale. It is not just another small Saturnian moon. It is a sample of how planetary systems can acquire outsiders and preserve them as companions. Phoebe makes Saturn's moon system feel less like a neat set of local products and more like a record of capture, migration, and leftover early material.
93.1km
Key facts
- Scale fact
- 213 kmmean diameter
- Composition
- Water ice, rock and dark carbon-rich material
Scale context
Where Phoebe sits on the full axis
Together, these objects make the size change around Phoebe easy to compare at a glance.
Sources
References for Phoebe
Measurements and descriptive context are compiled by the Scale of Space team from the references below. If you find an error, please let us know.
- Phoebe — Wikipedia
- Visual reference: Wikimedia Commons (NASA / JPL / Space Science Institute, Public domain)
Between the smallest and the largest, perspective is everything.
About
Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.
Guides turn parts of that scale into curated essays, while focused views let you explore the same range through specific groups of objects.