Facts About Planet Neptune – The Windiest Planet
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Neptune |
Facts about Neptune
Planet Profile
Name | Neptune |
---|---|
Knowm Satellite | 14 |
Distance from Sun (avg) | 4.495 billion km |
Equatorial Radius | 24,764 km |
Polar Radius | 24,341 km |
Volume | 6.254 × 1013 km3 |
Mass | 1.024 × 1026 kg |
Surface area | 7.618 billion km2 |
Gravity | 11.15 m/s2 |
Surface Temperature ( at 1 bar) |
-201 ℃ or -329 °F |
Length of day | 0 day 16 hrs 6 min (earth time) |
Length of year | 165 Earth years |
Astronomical symbol | ♆ |
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Quick Facts About Neptune
- Neptune is the only planet to have been discovered using mathematical calculations.
- All the moons of Neptune are named after Greek and Roman water gods.
- The first and only spacecraft to visit Neptune was NASA's Voyager 2 in 1989.
- The signal from Voyager 2 takes 246 days 4 hrs and 6 min to reach back to the Earth.
- It is so far that light from the sun takes about 4 hrs and 10 min to reach Neptune.
- Neptune has the third strongest gravity in the solar system, only after Sun and Jupiter.
- Like other gas giants, Neptune has also rings.
- Some part of the rings are brighter than others and appear as arcs.
- The magnetic field of Neptune is 27 times stronger than Earth's.
- Unlike other planets, whose magnetic field aligns with their axis, Neptune's magnetic field is tilted 47 ° from the planet's axis.
Detailed Facts about Neptune
Neptune was mathematically predicted before its direct observation
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Urbain Le Verrier (left) and John Couch Adams (right) |
On the evening of September 23, 1846, three years after Bouvard's death, Johann Gottfried Galle of Germany became the first man actually to see the distant world. He discovered Neptune at the Berlin Observatory by using the calculation from Le Verrier and with some help from his observatory student - Heinrich Louis d'Arrest. Galley was able to pinpoint the cause of Bouvard's deviations in Uranus's orbit. In 1846, the international astronomy community credited both Le Verrier and Adams as the discoverer of Neptune.
Neptune was named after the Roman God of sea and freshwater
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Neptune - Roman god of sea © Wikimedia |
After its discovery, Neptune was introduced as "the planet exterior to Uranus" and "Le Verrier's planet". Galle was the first to suggest a proper name for the planet. He put the name "Janus". In England, Challis, the director of Cambridge Observatory suggested the name "Oceanus". While Le Verrier wanted to name it as "Le Verrier" because he discovered it. Even he falsely claimed that his idea has been approved by the French Bureau. It was Friedrich Georg, a German astronomer who proposed the name "Neptune" in 1846.
Neptune is the smallest of the gas giants but still several times larger than Earth
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Neptune compared to Earth |
The equatorial circumference of Neptune measures around 96,685 miles or 155,600 kilometres. By comparison, Earth's circumference stretches just 25,000 miles or 40,000 kilometres. A road trip across Neptune's equator would have done at a steady pace of 60 mph or 96 km/h would take approximately 1600 hours or 67 days to cross.
Neptune is mainly made up of icy material
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Interiors of gas giant |
However, its neighbour Uranus is much lighter in colour which has even more methane than Neptune, about 2.5% compared to 1.5%. So, this suggests that there is another unknown component that gives Neptune its bright blue colour. Despite its colour, the planet experienced large dark spots or storms that have appeared and vanished from sight.
Neptune is the windiest place in the solar system
Researchers found that the Neptune's winds are so fast. That they frequently break the sound barrier, hitting speeds of up to 1500 miles or 2,400 kilometres per hour. The energy for making this whether coming from Neptune itself. It does receive sunlight but Neptune radiates away a lot more energy, about 2.6 times that it gets. Which means it has an internal source of heat that drives the fastest wind in the solar system.
There are currently 14 moons orbiting the planet
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Neptune's moons and their orbits |
- Triton - 1846
- Nereid - 1949
- Larissa - 1981
- Naiad - 1989
- Thalassa - 1989
- Despina - 1989
- Galatea - 1989
- Proteus - 1989
- Halimede - 2002
- Sao - 2002
- Laomedeia - 2002
- Neso - 2002
- Psamathe - 2002
- Hippocamp - 2013
Neptune is the most distant planet in the solar system
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Distance of Neptune and other planets from Sun © Wikimedia |
As it follows an elliptical orbit like other planets, this number varies throughout the years. When it is closest to the sun (perihelion), it is at a distance of about 4.46 billion km or 2.77 billion miles. At its farthest point (aphelion), it is around 4.54 billion km or 2.82 billion miles. It is no wonder that Voyager 2, the only spacecraft to observe Neptune up-close, took 12 years to reach the icy planet. Despite travelling at a speed of over 35,000 miles or 56,000 kilometres per hour.
Since its discovery, Neptune has only completed one orbit
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Orbits of Neptune and other outer planets with their positions |
It takes Neptune 165 earth years to complete its orbit around the Sun. A Neptunian year is much longer than any other planet. In fact, it was only in 2011 that the planet completed its first orbit since Johann Galle landmark observation. Due to Pluto's unusual orbit, sometimes it is closer to Sun than Neptune. However, Pluto is classified as a dwarf planet, Neptune remains the farthest planet in the solar system.
Neptune has also rings but they are much fainter than other gas giants
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Neptune's full rings image taken by Voyager 2 |
Despite covering a space of 77,500 miles or 125,000 kilometres the Rings are so faint. That a passing astronaut would be unable to see them with the naked eye. Instead at most, he would see a few bright arcs representing Neptune's outer narrow ring. Don't expect to see those rings for long they've been steadily deteriorating. With at least one expected to vanish by this next century.
Neptune is a very cold and very hot place
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Neptune's internal structure © Wikimedia |
Now with that, Neptune has an extremely hot core that produces temperatures hotter than the surface of our Sun, about 7,000 ℃ or 12,600 °F. Neptune's core is so hot that it generates most of the planet's heat as opposed to relying on the Sun upon. So Neptune is an icy planet filled with Sun scorching warmth.
Neptune experiences huge disappearing storms
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Neptune's Great Dark Spot |
It is unknown to us whether this storm still exists on Neptune because Hubble observations are limited. A program has begun called the Outer Planet Atmospheres Legacy or OPAL to gather global maps of our gas giant planets every year. We really don't know why large storms on Neptune form and dissipate much more rapidly than storms on Jupiter.
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