Astr110 Photography Projects, Fall 2004

Neptune, John Watkins

Neptune is the eigth planet from the sun in our solar system. It is 30.06 Au away from the sun and is the fourth largest planet with a diameter of 49,532 km. There are13 known moons that orbit around this bluish planet and there are also rings of unknown composition around its diameter. Neptune is a gas planet that is made up of "ices", rock, 15% hydrogen and also a small amount of helium. Similar to Uranus, Neptune is thought to have a composition that is rather uniform throughout the entire planet except for the small rocky core. Neptune's atmosphere is made up of hydrogen, helium, and a small amount methane.

It is this methane gas that gives Neptune its most obvious feature. As seen in the picture, Neptune has a very noticeable bluish color. Methane absorbs the red light received from the sun. Besides the fact that it is a lot brighter and larger, it is the wonderfully blue color that stands out the most in the picture above.

References:
http://www.nineplanets.org/neptune.html