Neptune Data


Discovered by Johann Galle in 1846


Average Distance from the Sun

Metric: 4,498,252,900 km

English: 2,795,084,800 miles


Perihelion (closest)

Metric: 4,459,630,000 km

English: 2,771,087,000 miles


Aphelion (farthest)

Metric: 4,536,870,000 km

English: 2,819,080,000 miles


Equatorial Radius

Metric: 24,764 km

English: 15,388 miles


Equatorial Circumference

Metric: 155,597 km

English: 96,683 miles


Volume

Metric: 62,526,000,000,000 km3


Mass

Metric: 102,440,000,000,000,000,000,000,000 kg


Density

Metric: 1.76 g/cm3


Surface Area

Metric: 7,640,800,000 km2

English: 2,950,100,000 square miles


Equatorial Surface Gravity

Metric: 10.71 m/s2

English: 35.14 ft/s2


Escape Velocity

Metric: 85,356 km/h

English: 53,038 mph


Sidereal Rotation Period (Length of Day)

0.67125 Earth days

16.11 hours


Sidereal Orbit Period (Length of Year)

164.79 Earth years

60,190 Earth days


Mean Orbit Velocity

Metric: 19,720 km/h

English: 12,253 mph


Orbital Eccentricity

.00859


Orbital Inclination to Ecliptic

1.769 degrees


Equatorial Inclination to Orbit

29.58 degrees


Orbital Circumference

Metric: 28,142,000,000 km

English: 17,487,000,000 miles


Effective Temperature

Metric: -214 °C

English: -353 °F


Atmospheric Constituents

Hydrogen 85%

Helium 13%

Methane 2%


Moons:

1. Naiad

2. Thalassa

3. Despina

4. Nereid

5. Galatea

6. Larissa

7. Proteus

8. Triton

9. S/2002 N1

10. S/2002 N2

11. S/2002 N3

12. S/2002 N4

13. S/2003 N1