Did you know that Neptune's core is the size of Earth. Neptune is made up of various ice and rock and its mostly gases and liquids. Just like jupiters big red spot neptune has a great blue spot.The tempenture of neptunes core is at a blazing 7,000 (C). The atmosphere's tempenture is -218 (c). Neptune cannot be seen by the naked eye, but with the help of a vision enhancing device, it can. Neptune is so far away, that it took 12 years to for the spacecraft "Voyager 2" to reach it. When it did, it appeared right away that neptune was a a very stormy planet. There has been only one spacecraft to ever visit Neptune, which was "Voyager 2", which was on Aug 25 1989. Most of the things we know about Neptune come from this single mission. Neptune also has very fast winds, sometimes reaching up to 700 mph. The composition of Neptune's rings still remain a mystery. The reason for Neptune's blue color is the absorption of red light by Methane in the atmosphere. Neptune has an internal heat source, so it radiates twice as much energy as it receives from the Sun.