Dark, cold and whipped by supersonic winds, giant Neptune is the eighth and most distant major planet orbiting our Sun. More than 30 times as far from the Sun as Earth, Neptune is not visible to the naked eye. In 2011, Neptune completed its first 165-year orbit since its discovery.
The planet’s rich blue color comes from methane in its atmosphere, which absorbs red wavelengths of light but allows blue ones to be reflected back into space.
Neptune was the first planet located through mathematical calculations. Using predictions sent him by French astronomer Urbain Le Verrier, based on disturbances in the orbit of Uranus, German asstronomer Johann Galle was first to observe the planet in 1846. The planet is named after the Roman god of the sea, as suggested by Le Verrier.