Universe Today
[/caption] The following Neptune fact sheet is based on
NASA's excellent planetary fact sheets
. Neptune is the 8th planet from the Sun, and it requires a telescope to be able to see it.
Mass: 102.43 x 10
24
kg
Volume: 6,254 x 10
10
km
3
Average radius: 24,622 km Average diameter: 49,244 km Mean density: 1.638 g/cm
3
Escape velocity: 23.5 km/s Surface gravity: 11.15 m/s
2
Natural satellites: 13
Rings? - Yes
Semimajor axis: 4,495,060,000 km
Orbit period: 60,189 days
Perihelion: 4,444,450,000 km
Aphelion: 4,545,670,000 km
Mean orbital velocity: 5.43 km/s
Orbit inclination: 1.769°
Orbit eccentricity: 0.0113
Sidereal rotation period: 16.11 hours
Length of day: 16.11 hours
Axial tilt: 28.32°
Discovery: 23 September 1846
Minimum distance from Earth: 4,305,900,000 km
Maximum distance from Earth: 4,687,300,000 km
Maximum apparent diameter from Earth: 2.4 arc seconds
Minimum apparent diameter from Earth: 2.2 arc seconds
Maximum visual magnitude: 7.78
We've written many articles about Neptune for Universe Today. Here's an article about the
color of Neptune
, and here's an article about
the atmosphere of Neptune
.
If you'd like more info on Neptune, check out
Hubblesite's News Releases about Neptune
, and here's a link to
NASA's Solar System Exploration Guide to Neptune
.
We've also recorded an entire episode of Astronomy Cast just about Neptune. Listen here,
Episode 63: Neptune
.
