Post facts and photos of astronomical phenomena.

15 Interesting Facts About Neptune That'll Rock You to the Core

Interesting Facts About Neptune
How was Neptune discovered? How did it get its name? What is Neptune composed of? Which color is Neptune? How many moons and rings does it have?
Priya Johnson
Last Updated: Feb 17, 2018
Diamonds falling
Neptune, also known as the 'Blue Giant' is the eighth planet from the Sun, situated between Uranus and Pluto. However, sometimes Pluto is seen to cross its path, and then it becomes the ninth planet from the Sun. Neptune is 49500 km in diameter, and is four times the size of the Earth, however, since it is approximately 4.4 billion km away from the Earth, it is not easily visible through binoculars.
How was Neptune discovered?
solar system
In case of the other planets, telescopes found them, however, in case of Neptune, the mathematical calculations lead to the planet's discovery. Several astronomers, including Galileo had seen Neptune, little realizing that they were looking at another planet. This was because, through the telescopes, planets appeared to look like discs, and stars appeared as spots of bright light. The telescopes were not powerful enough to show Neptune's disc shape. In 1781, William Hershel discovered planet Uranus and after Uranus' discovery, astronomers began to wonder if there was another planet beyond Uranus. In 1843, John C. Adams, a young British mathematician and astronomer set forth to calculate the position of Neptune. According to his calculations, Neptune was 1 billion miles further away from the Sun, than Uranus.

He sent his findings to the astronomer royal of England, Sir George B Airy, in 1845. But to Adams dismay, Airy did not respond to his findings. However, Adams was not the only one working on Neptune's calculations. Urbain Jean Joseph Le Verrier, a French astronomer and mathematician was also diligently calculating the location of Neptune. In 1846, he too came up with the same results as Adams, and sent his findings to Johann G. Galle of Germany. Galle had also been working on the location of the planets, and with the help of Urbain's predictions, he along with his assistant found the planet Neptune on September 23rd 1846.

However, after the discovery, conflicts between UK and France arose, over who should be credited with the discovery of Neptune. The international astronomy community decided to give the credit to both Adams and Urbain for Neptune's discovery. Isn't this an interesting fact about Neptune?
How did Neptune get its name?
statue of neptune
Neptune is the Roman counterpart of the Greek God Poseidon
The naming ceremony of Neptune has an interesting story. Urbain J.J. Le Verrier felt that since he discovered the planet, he had the right to name it after himself. However, his desire was trampled by people outside France. Since, all the other planets were named after Roman Gods, the international astronomy community came to a consensus that this planet should also be named after a Roman God. Thus, Neptune, being a blue planet was named after the Roman God of the sea.
Composition of Neptune
neptune and its core and mantle
The mantle region is extremely hot, with temperatures ranging from 3000K to 5000K
Neptune's hot rocky core is approximately the size of the earth and is made up of nickel, iron and other silicates. Beyond the core, is the large mantle comprising methane, ammonia, water and other compounds. This mantle region is extremely hot, with temperatures ranging from 3000K to 5000K, thus this region corresponds to a superheated liquid region. Beyond the mantle is the outermost atmosphere which is made up of gases like Hydrogen (80%), Helium (19%) and (1%) Methane, Ammonia and water.
Neptune: The Windiest Planet
neptune and its rings
The energy to generate these winds comes from Neptune's internal heat source
Neptune has extraordinary weather and is the most windy planet in our solar system. Logically speaking planets further away from the Sun must have weaker winds, because wind is driven by the Sun's energy and planets that receive less sunlight should have weaker winds. However, Neptune has extremely strong winds, which can reach speeds of about 2,000 kilometers per hour.
A hurricane on earth would approximately reach a speed of 200 kilometer per hour, so one can imagine the magnitude of these wind storms. The energy to generate these winds comes from Neptune's internal heat source.
Why is Neptune blue in color?
neptune and its blue color
Neptune's color is nothing but reflected sunlight minus red end of the spectrum
Neptune is a gas planet (like Jupiter, Saturn and Uranus), and its upper atmosphere is made up of gases such as Hydrogen, Helium, Methane, Ammonia, and water. Methane on Neptune's surface absorbs light coming from the Sun at 600nm, which corresponds to the red region of the visible light spectrum. Therefore, methane absorbs red light and reflects blue end of the spectrum back into space. This is how Neptune gets its azure blue color.
Weather Patterns on Neptune
neptune with the great dark spot
Neptune with The Great Dark Spot
As per the information obtained from Voyager 2's visit to Neptune in 1989, Neptune exhibits distinct weather patterns. It observed an extremely massive anticyclonic storm system, which appeared as a massive dark spot on the surface (southern hemisphere) of the planet. The series of dark spots observed is known as the Great Dark Spot, of which the largest corresponds to the size the Earth.
This Great Dark Spot is surrounded by white cirrus clouds of methane. Then Voyager 2 also spotted smaller spots, called scooters, which move rapidly across the surface of the planet.
Moons of Neptune
neptune and its moon triton
Neptune and its first moon, Triton
17 days after the planet Neptune was discovered, an astronomer named William Lassell discovered Neptune's first moon, Triton. Triton is 2707 km in diameter, and had it been orbiting the Sun, instead of Neptune, then it could have been called a planet. The orbit of Triton is retrograde, which means it orbits in the opposite direction to the planet's rotation. This is also indicative of the fact that Neptune actually captured Triton.
An interesting fact about Neptune's Triton is that Triton's surface temperature is only 38 Kelvin, which makes Triton one of the coldest regions of the solar system. Voyager 2 (USA) visited Neptune in 1989, and is the only spacecraft to have visited the planet. It discovered geysers of blasting nitrogen on Triton's surface. Even though it took only seventeen days after the planet's discovery to find Triton, the second moon was discovered only 100 years later, in 1949. As of today, 13 of Neptune's moons have been discovered, all of which are named after Gods from Greek mythology.
Rings of Neptune
neptune and its rings
The 5 rings are named Galle, Le Verrier, Lassell, Arago, and Adams
With the help of the images captured by Voyager 2, we have come to know that Neptune possesses 5 faint rings. These 5 rings are named Galle, Le Verrier, Lassell, Arago, and Adams: astronomers who were involved with discoveries related to Neptune. These rings are relatively new to the Solar System, and are younger than Uranus' rings. Astronomers believe that the rings were formed when one of Neptune's moons got too close to the planet and disintegrated due to gravity.
Length of Day and Year on Neptune
Neptune Planet
While Earth takes 365 days to complete a revolution round the sun, Neptune takes 60,190 days
What's interesting about Neptune is that different parts of the planet rotate at a different pace. The polar regions of the planet take 12 hours to complete one rotation, whereas the equatorial region takes 18 hours to complete one rotation. On an average, the planet takes 16 hours to complete a day.
A day on Neptune is shorter than a day on the Earth, however, a year on Neptune is longer than a year on the Earth. This is because Neptune orbits the Sun at an average distance of 4.5 billion kilometers. Where the Earth takes 365 days to complete one rotation, Neptune takes 60,190 days to revolve around the Sun once. So a year on Neptune is 165 Earth years.
Water is present on Neptune, so is there a possibility of life on Neptune? Scientists say that since there is water, technically life should exist, however, the surface of Neptune is far too cold for any living organism to exist (water turns to ice). But, the planet gets hotter towards the core, so can life exist at the point at which the planet is neither too hot, nor too cold (where water exists in liquid form). This is still something scientists are working on. Till they come up with the answer, we can cling on to these interesting facts about Neptune.
Neptune planet 3d vector illustration
Cartoon Neptune Sign