The Blue Planet, as it is often known by, is the eighth planet from the sun and named after the Roman god of the seas, Neptune. However, it wasn’t until the discovery of the planet Uranus that Neptune’s story truly begins.
In the middle of the 19th century, the Englishman John Crouch Adams and the Frenchman Urbain le Verrier started to calculate predictions for when a mysterious planet might be located. For some time, it was believed that there was a distant planet that was affecting the orbit of the planet Uranus.
As both were astronomers and mathematicians, they calculated as to where this planet might be located, although they had increasing difficulty in gaining the support of others in their fields. On 23 September 1846, using the calculations Crouch Adams and le Verrier predicted, Johann Gottfried Galle and Heinrich d’Arrest discovered it nearby. Neptune was thus then the first planet to be found by maths.
Although Gottfried Galle and d’Arrest were the first to find Neptune, the discovery of it was actually given to Crouch Adams and le Verrier after heated debates. However it has recently been understood that Neptune had actually been see earlier by Galileo and other people, but had not recognised the planet for what it actually was.
Scientists have tried to study the Blue Planet but being so far away it has been met with some difficulty. From the ground, scientists have determined its size (17.147), its orbit (165 Earth years to go around the sun) and what the atmosphere is generally made up from (80% hydrogen, 19% helium, plus traces of methane, ethane and hydrogen deuteride). Within 17 days of its discovery, scientists identified one of its moons, Triton, but no more would be found for more than a century.
When NASA’s Voyager 2 probe reached Neptune in 1989, scientists were able to really start studying this mysterious planet. Initially, people thought that the planet was a ball of inactive gas but instead Neptune was found to have some of the fastest winds in the Solar System, reaching speeds of up to 1,300 mph (2,100 km/h).
Neptune has 13 moons, Triton being the largest. Triton is the coldest, its surface covered in ice and very reflective. What makes Triton interesting is the fact that it has a retrograde orbit; this means ir orbits Neptune the wrong way.
Scientists did not know how reflective triton was until Voyager 2 came closer when they found that it was, in fact, one of the shiniest objects in the Solar System. At -391 F (- 235 C) it is also one of the coldest.
Triton is a relatively body with only a few craters visible. Scientists believe it is made up of 25% ice and then made up of rocky material with a thin atmosphere of made up of nitrogen. What is truly amazing at Triton is that there are volcanoes which spew up liquid nitrogen (or so scientists believe), caused by the sun’s seasonal heating.
Scientists have speculated that Triton’s retrograde orbit may have been cause due to its not being formed with Neptune, but it was ‘captured’ as it drifted past the planet. It could be that Triton was part of a double planetoid system and then hurled away.
Neptune has several other moons, the third largest being Neredid, found in 1949. After Voyager 2’s contact with Neptune, scientists discovered six more in 1989 which, like Triton, have retrograde orbits. Scientists believe that they were captured like Triton and not formed with Neptune.
Neptune has a system of rings like other planets in the Solar System and was first made apparent in the 1980s. They were discovered with astronomers noticed a background star flashing when Neptune past in front. When the planet wasn’t quite in front of these stars, they would dip, leading to the theory that the planet had rings. It wasn’t until Voyager 2 that this would be confirmed.
Scientists believe that these rings may not actually be stable and might actually fall apart within the next century or so.
The Blue Planet is called this because if it’s beautiful blue colour. It gets this tone from the little quantities of methane in its atmosphere. How it works is that the methane absorbs the red wavelights from the sun and reflects only the blue. Scientists still cannot account for the darker shades of blue.
57 times larger than the Earth, Neptune has a mass 17 times that of the Earth’s. Scientists have speculated that it is a planet with a core of rock and ice over earth. It is believed that Neptune came into being around 4.5 billion years ago.
With a temperature of somewhere around – 353 F (- 241 C), Neptune may be considered a cold place but the mysteries awaiting scientists leave nothing but warm thoughts, hopes and dreams.