Using information from Le Verrier, Johann Galle saw Neptune for the first time on September twenty-third, eighteen forty-six. A British astronomer named John Couch Adams had also predicted Neptune’s position in space. Both are given credit for first predicting the position.
BARBARA KLEIN: Neptune is named for the Roman god of the sea. The planet's orbit lies about four billion five hundred million kilometers from the sun. That is about thirty times further away than Earth. Neptune is the most distant member of our solar system. It cannot be seen from Earth without the aid of binoculars or a telescope.
The planet’s atmosphere is made up mostly of hydrogen, helium and methane. Its blue-green color is caused by methane gases in the outer atmosphere.
Most of what we know about Neptune comes from NASA's Voyager Two spacecraft. It was the first and only space probe to visit the planet in nineteen eighty-nine.
MARIO RITTER: Thirteen known moons circle Neptune. The largest of these is called Triton. It was discovered just days after Neptune’s discovery in eighteen forty-six. Voyager Two discovered six of the moons during its flight around the planet. It also confirmed the existence of rings around the planet.
Neptune is one of four planets known as the gas giants. The other three are Jupiter, Saturn and Uranus. These planets are made up almost entirely of gas. They are also four to twelve times the size of earth.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25