This view of Uranus was recorded by Voyager 2 on 25 January 1986, as the spacecraft left the planet behind and set forth on the cruise to Neptune. Voyager 2 was 1 million kilometres from Uranus when it acquired this wide-angle view. The picture – a colour composite of blue, green and orange frames – has a resolution of 140 km. The thin crescent of Uranus is seen here at an angle of 153 degrees between the spacecraft, the planet and the Sun. Even at this extreme angle, Uranus retains the pale blue-green colour seen by ground-based astronomers and recorded by Voyager during its historic encounter. This colour results from the presence of methane in Uranus’ atmosphere; the gas absorbs red wavelengths of light, leaving the predominant hue seen here. The tendency for the crescent to become white at the extreme edge is caused by the presence of a high-altitude haze. Credit: Nasa/JPL
Launched on 20 August 1977, Voyager 2 is the longest operating spacecraft, past or present. It is 15 billion kilometres away from our Sun. Launched on 5 September 1977, Voyager 1 is the most distant human-made object, at about 18 billion kilometres away from our Sun. The two Voyager spacecraft have been travelling through our solar system for 35 years and are still sending back data as they draw close to crossing into interstellar space, which is the space between stars.
Download wallpaper images of a selection of photos from the Voyager encounters with Jupiter, Saturn, Uranus and Neptune…
The twin Voyager spacecraft won the Mechanical Lifetime Achievement Award in the Popular Mechanics 2012 Breakthrough Awards. Get your hands on PM’s Dec ’12 issue – on sale on 19 November – to find out about the best bold ideas of 2012.