Reference image
Proteus moon solar system object
Object guide

Proteus is one of Neptune's larger inner moons; it has an irregular shape and heavily cratered surface. Proteus is approximately 420 km across.

How to observe Proteus

Proteus is resolved as a separate world mainly through imaging or spacecraft data; visually, its relationship to neptune is the key observing context.

Scientific context

Useful scale comparisons are 0.033 Earth diameters, 0.006 g surface gravity, 0.003 Earth years per orbit. These values are rounded from the catalogue measurements shown on this page.

Radius
210 km
Diameter
420 km
Mass
5,000,000,000,000,000,000 kg
Mean density
0.129 g/cm³
Surface gravity
0.06 m/s² (0.006 g)
Orbital period
1.122 days (0.003 years)
Parent body
neptune
0.033 Earth diameters0.006 g surface gravity0.003 Earth years per orbit

Source: NASA Science ↗

Parent planet in the solar system

The overview shows Neptune, the parent planet. This moon is not rendered in the heliocentric model.

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