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- Moon Name: Proteus
- Designation: Neptune VIII
- Date Discovered: June 16th, 1989
- Discovered by: S. Synnott (Voyager 2)
- Average Orbit of Neptune: 73,101.83 mi
- Total Volume: 9,306,788 mi3
- Surface Area: 213,968.91 mi2
16 Proteus Facts for Kids
- Proteus is one of Neptune’s 14 known moons (natural satellites).
- Proteus is named after the Greek mythology god Proteus, who was a shape-changing sea creature.
- Proteus is also designated Neptune VIII.
- Proteus was discovered on June 16th, 1989 by American astronomer Stephen P. Synnott.
- Proteus was discovered from photographs taken by Voyager 2 in August 1989.
- Proteus wasn’t discovered by Earth-based telescopes due to its close distance to Neptune and dark surface.
- Proteus was the third moon to be discovered orbiting Neptune.
- Prior to the discovery of Proteus, it had been 33 years since a moon orbiting Neptune had been discovered.
- The average orbit distance for Proteus is 73,101.83 mi.
- The surface area of Proteus is 213,968.91 mi2.
- The total volume of Proteus is 9,306,788.33 mi3.
- Proteus orbits the planet Neptune every 26.55 hours.
- Proteus is the second largest moon of Neptune, based on diameter.
- Proteus is the seventh closest moon to Neptune.
- Proteus is one of the darkest moons in our Solar System and only reflects around 10% of the Sun’s light.
- The largest crater on Proteus is named Pharos and has a diameter of 140 mi.
Additional Resources on Neptune’s moon Proteus