Jupiter’s satellite Io
This full-disc image of Jupiter’s satellite Io was made from several frames taken by Voyager 1 on 4 March 1979, as the spacecraft neared the satellite. Io is about 862 000 km away here. A variety of features can be seen in the photo that appear linked to the intense volcanic activity on Io: the circular, doughnut-shaped feature in the centre has been identified with a known erupting volcano; other, similar features can be seen across the face of the satellite. Io’s volcanic activity appears to be of at least two general kinds – explosive eruptions that spew material into the sky as much as 250 km altitude; and lava that flows from vents across the surface. Io is the first body in the solar system (beyond Earth) where active volcanism has been observed. 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.