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Comparison Chart
Comparison: Proteus vs. Neptune

This chart shows the differences between Proteus and Neptune. To change the planets/moons being compared, change one or more of the form fields at the bottom and click Refresh.

Discovered By
S. Synnott, Voyager 2
Urbain Le Verrier, John Couch Adams, Johann Galle
Date of Discovery
23 September 1846
Average Orbit Distance
117,646 km
4,498,396,441 km
Perihelion/Perigee (closest)
117,587 km
4,459,753,056 km
Aphelion/Apogee (farthest)
117,705 km
4,537,039,826 km
Equatorial Radius
210.0 km
24,622 km
Equatorial Circumference
1,319.5 km
154,704.6 km
38,792,386 km3
62,525,703,987,421 km3
50,355,259,352,065,700,000 kg
102,410,000,000,000,000,000,000,000 kg
1.3 g/cm3
1.638 g/cm3
Surface Area
554,176.94 km2
7,618,272,763 km2
Equatorial Surface Gravity
0.76 m/s2
11.15 m/s2
Escape Velocity
644 km/h
84,816 km/h
Orbit Period (Length of Year)
0.003071869 sidereal years
164.79132 sidereal years
Mean Orbit Velocity
27,450.7 km/h
19,566 km/h
Orbit Eccentricity
Orbit Inclination to Ecliptic
0.075 degree
1.77 degrees
Orbit Circumference
739,191.57 km
28,263,736,967 km


New planets/moons to compare:

System of measurement:

Compare All Eight Planets

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Last Updated: 28 Apr 2014