Neptune Statistics

Planetary Symbol: Name in Roman/Greek Mythology: Neptune/Poseidon
Diameter: 49,493 km (30,760 miles) Rotation Period about Axis: 17.24 hrs
Mass: 102.4x10^24 kilograms (17.2 x Earth's) Revolution Period about the Sun: 165 years
Density: 1,638 kg/m^3 Tilt of Axis: 29o 36"
Minimum Distance from Sun: 4.46 billion km
(2.77 billion miles)
Surface Gravity: 11 m/s^2 (1.12 x Earth's)
Maximum Distance from Sun: 4.54 billion km
(2.82 billion miles)
Temperature at Cloud Tops: -210o C ( -346o F)
Orbital Semimajor Axis: 30.07 AU (Earth=1 AU) Average Cloud Top Temperature (K): 63K
Minimum Distance from Earth: 4.3 billion km
(2.68 billion miles)
Satellites/Rings: known moons, faint rings

Neptune Image Archive

Comparative Planetary Statistics -- in table form

Comparative Orbital Statistics -- in table form

Actual Distance to Earth

Last modified October 31, 2003 by Randy Russell.

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