Solar system

The planet Neptune: blue, distant and windy

The planet Neptune: blue, distant and windy

Neptune It is the outermost planet of the gas giants and the first that was discovered thanks to mathematical predictions.

The eighth planet of the Solar System owes its name to the Roman god Neptune, lord of all waters. Its equivalent in Greek mythology is Poseidon.

It is the fourth and furthest of the giant gas planets. The last two, Uranus and Neptune, are known as frozen giants, because of its low temperatures. It is also the fourth largest planet in size and third in mass, equivalent to about 17 times that of our planet.

The following table shows data from Neptune compared to Earth:

Basic dataNeptuneThe earth
Size: equatorial radius24,622 km.6,378 km.
Average distance to the Sun4,498,252,900 km.149,600,000 km.
Day: period of rotation on the axis 16.11 hours23.93 hours
Year: orbit around the Sun164.8 years1 year
Average surface temperature-220 º C15 º C
Surface gravity in the equator11 m / s29.78 m / s2

The interior of Neptune is rock melted with water, methane and liquid ammonia. Outside, methane abounds, which gives it its characteristic blue color. Neptune is a little smaller than Uranus, but denser.

Its magnetic field is inclined 47 degrees from the axis of rotation of the planet and displaced about 13,500 km from the physical center. This orientation may be due to the flows inside and not the inclination of the planet itself.

Neptune also has rings

The Voyager II ship approached Neptune in 1989 and photographed it. He discovered six of his eight moons and confirmed the existence of rings.

Indeed, Neptune has a system of four narrow, thin and very thin rings, difficult to distinguish with ground telescopes. The rings were formed from dust particles, torn from the interior moons by the impacts of small meteorites.

What is the atmosphere of Neptune like?

The atmosphere has some spots that remind of Jupiter's storms, but, unlike this, in Neptune they form and disappear frequently. The largest, the Great Dark Spot, had a size similar to that of the Earth, but in 1994 it disappeared and another was formed.

The strongest winds of any planet in the Solar System are those of Neptune. Many of them blow in the opposite direction of rotation. Winds of 2,000 km / h were measured near the Great Dark Spot.

The photo above shows the appearance of Neptune from 1996 to 2002. More recent observations have also detected changes like these.

In the atmosphere of Neptune it reaches temperatures close to 260 ° C below zero. It contains, above all, hydrogen and helium, along with some nitrogen. Water, ammonia and methane ice abound. Most clouds are frozen methane and change rapidly.

The discovery of Neptune

Galileo saw Neptune in 1612, but confused him with a star. They had to spend more than two centuries until their official "discovery". At the beginning of the 18th century, several astronomers observed that the newly discovered orbits of Jupiter, Saturn and Uranus did not have the behavior described by the laws of Kepler and Newton. Beyond there had to be an eighth planet.

Adams and Le Verrier, an Englishman and a Frenchman, independently calculated where the hypothetical planet should be, and they were right. The German astronomer Johann Gottfried Galle, at the request of Le Verrier, observed the region indicated by the calculations and found Neptune on September 23, 1846.

The distance that separates us from Neptune can be better understood with two data: a ship has to make a trip of twelve years to arrive and, from there, its messages take more than four hours to return to Earth.

Discover more:
• Five mysteries that Neptune hides
• Neptune's rings

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