Our solar system's most distant major planet, Neptune, has arrived at the same location in space where it was first discovered 165 years ago. To commemorate the event, NASA's Hubble Space Telescope has taken images of the blue-green giant planet.
Neptune was first discovered 165 years ago and now has completed one full orbit around the Sun. To celebrate this milestone, astronomers used Hubble's Wide Field Camera 3 to take a closer look at the planet. Images reveal high-altitude clouds composed of methane ice crystals. The methane absorbs red light resulting in the planet's aqua color. The clouds look pink because they are reflecting near-infrared light.
This video sequence compiles data from Hubble's observations of Neptune to show the blue-green planet rotating on its tilted axis. A day on Neptune is 16 hours long, and Hubble took images of the planet every four hours.
Publication: July 12, 2011