Neptune
The eighth and officially farthest planet from the Sun, Neptune is the smallest but most dense of the gas giants. Dark, cold, and whipped by supersonic winds, this ice giant is a dynamic world with a turbulent atmosphere.
Equatorial Diameter
49,528 km
Surface Temperature
-200°C
Mass
1.024 × 10^26 kg
Surface Gravity
11.2 m/s²
Rotation Period
16h 06m
Orbital Period
165 years
Planetary Structure & Atmosphere
Neptune's vivid blue color is more intense than that of Uranus, and while it's caused by methane, an additional unknown component is presumed to create its intense hue. The planet generates significant internal heat through poorly understood processes, which drives the fastest winds in the Solar System. The planet's fluid mantle has high electrical conductivity, giving rise to its magnetic field.
Scientific Discoveries
- Neptune was the first planet to be discovered purely on the basis of mathematical prediction rather than by direct observation. Since its discovery in 1846, it has completed only one orbit of the Sun.
- Its internal heat drives the strongest winds in the solar system, which can reach up to 2,100 km/h and generate gigantic storms.
- Neptune is the smallest but also the most dense of the gas giants, with a surface gravity surpassed only by Jupiter.
- Like Uranus, it is theorized that Neptune may have an ocean of super hot, liquid carbon where "diamond-bergs" float.
- Its largest moon, Triton, is colder than Pluto and orbits the planet backwards (retrograde orbit).
- A massive storm called the "Great Dark Spot," was seen by Voyager 2 but had vanished when Hubble checked in 1994, showing how dynamic its atmosphere is.