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Atmospheric features on Neptune
Voyager 2 captured this convergence of atmospheric features on Neptune.
Neptune:

The eighth planet from the Sun, Neptune was the first planet located through mathematical predictions rather than through regular observations of the sky. When Uranus didn't travel exactly as astronomers expected it to, two mathematicians, working independently of each other, proposed the position and mass of another, as yet unknown planet that could account for Uranus' orbit. Although "the establishment" ignored the predictions, a young astronomer decided to look for the predicted planet. Thus, Neptune was discovered in 1846. Seventeen days later, its largest moon, Triton, was also discovered.

Nearly 4.5 billion kilometers from the Sun, Neptune orbits the Sun once every 165 years, and therefore it has not quite made a full circle around the Sun since it was discovered. It is invisible to the naked eye because of its extreme distance from Earth. Interestingly, due to Pluto's unusual elliptical orbit, Neptune is actually the farthest planet from the Sun for a 20-year period out of every 248 Earth years.

Read More About Neptune

Just the Facts
Distance from the Sun: 
4,498,252,900 km
Equatorial Radius: 
24,764 km
Volume: 
62,526,000,000,000 km3
Mass: 
102,440,000,000,000,000,000,000,
000 kg
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