NASA powers down instruments on Voyagers to save power

Last week, NASA powered down an instrument on Voyager 1 designed to study cosmic rays. 

The energy-saving moves were necessary to extend their missions, Voyager project manager Suzanne Dodd at the NASA Jet Propulsion Laboratory said in a statement. 

The twin spacecraft launched in 1977 and are currently in interstellar space, or the space between stars.

Voyager 1 discovered a thin ring around Jupiter and several of Saturn's moons, and Voyager 2 is the only spacecraft to visit Uranus and Neptune. 

Each spacecraft still has three instruments apiece to study the sun's protective bubble and the swath of space beyond.

Voyager 1 is over 24 billion kilometres from Earth, while Voyager 2 is more than 20.9 billion kilometres away.