Key facts
- Mean diameter
- 2,706.8 km
- Mass
- 2.14 × 10^22 kg (0.00358 Earths)
- Surface gravity
- 0.779 m/s² (0.0794 g)
- Escape velocity
- 1.45 km/s
- Mean temperature
- -235 °C
- Rotation period
- 141.05 hours
- Orbital period
- 5.877 days (retrograde)
- Mean distance from Neptune
- 0.35476 million km
Atmosphere
Negligible or extremely thin.
Composition and structure
Rock and ice.
Discovery and exploration
Imaged by Voyager 2 in 1989; likely a captured Kuiper Belt object.