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Neptune Facts
- Neptune is the eighth and farthest planet from the Sun in the Solar System.
- It is classified as an ice giant, composed mainly of hydrogen, helium, and ices like water, ammonia, and methane.
- Neptune has a diameter of about 49,244 km (30,598 miles), making it the fourth-largest planet by diameter and third-largest by mass.
- Its atmosphere is primarily hydrogen and helium with trace amounts of methane, which gives it a blue color.
- Neptune has a system of faint rings and 14 known moons, the largest of which are Triton, Nereid, Naiad, Thalassa, and Despina.
- It has the strongest sustained winds of any planet in the Solar System, with wind speeds reaching up to 2,100 km/h (1,300 mph).
- Neptune has a tilted magnetic field, with its magnetic poles offset from its rotational axis by 47 degrees.
- The planet's atmosphere exhibits dynamic weather patterns, including large storms and high-speed jet streams.
- It was discovered in 1846 by Johann Galle and Urbain Le Verrier through mathematical predictions based on irregularities in Uranus' orbit.
- Neptune has a thick atmosphere that consists mainly of hydrogen, helium, and methane gas.
- It orbits the Sun once every 164.8 Earth years at an average distance of about 4.5 billion kilometers (30.1 AU).
- Neptune's temperature can drop to -218°C (-360°F), making it one of the coldest places in the Solar System.
- NASA's Voyager 2 is the only spacecraft to have visited Neptune, passing by the planet in 1989 and providing detailed images and data.
- Neptune's blue color comes from methane in its atmosphere absorbing red light and reflecting blue.
- Scientists believe Neptune has a rocky core surrounded by a deep layer of ice and a thick atmosphere of gases.
- Future missions may explore Neptune further to study its moons, rings, and complex weather systems.
- Neptune is not visible to the naked eye and requires a telescope to observe.
- Its moon Triton has geysers that eject nitrogen gas and dust particles into space.