Neptune was named after the Roman God of the sea. However, in Greek mythology; Neptune was said to be linked to the Greek God, Poseidon. This planet was discovered in 1845-46 by one Urbain Le Verrier who wants it named after him. However people outside of France which was Urbain Le Verrier’s native country, felt that the naming of planets should be kept to the nomenclature of other planets which were of course with regards to the Greek and Roman mythology.
Neptune is the eighth planet from the Sun in the solar system and also the fourth largest planet in terms of diameter as well as the third largest in terms of mass. Due to its large distance from the Sun, the temperature on the planet is really low sometimes reaching towards -218°C (55K). However, the temperature at the centre of the planet is approximately 5000°C (5400K). The mass of the planet is at 1.0243 × 1026 kg, which is seventeen times the mass of Earth. The main composition of this planet is made of gas. For example, according to data collected by Voyager 2, the atmosphere is saturated with methane and ammonia.
Neptune exudes a blue hue due to the fact that methane absorbs red light. Basically, the atmosphere of Neptune could be subdivided into two main regions which are the lower troposphere where temperature decreases with altitude and the stratosphere, where temperature increases with altitude. Models suggest that Neptune’s troposphere is banded by clouds of varying compositions depending on altitude. The upper-level clouds occur at pressures below one bar, where the temperature is suitable for methane to condense. For pressures between one and five bars (100 and 500 kPa), clouds of ammonia and hydrogen sulfide are believed to form. Above a pressure of five bars, the clouds may consist of ammonia, ammonium sulfide, hydrogen sulfide and water. Deeper clouds of water ice should be found at pressures of about 50 bars (5.0 MPa), where the temperature reaches 0 °C.