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Voyager 2 finally says 'hello' back to Nasa

An illustration of Voyager 2Image source, MPI
Image caption,

An illustration of Voyager 2

Scientists who hadn't been able to command space probe Voyager 2 for the past eight months, have been back in contact with it.

It's because the radio antenna - Deep Space Station 43 in Australia - had to be turned off for major repairs. It's the only dish in the world that can send commands to Voyager 2.

On 29 October test messages were sent and the probe 'picked up' the cosmic call, and carried out its commands without any problem.

It took a while though, the team had to wait more than 34 hours for a reply, much longer than the 16 hours it usually takes.

The probe has still been sending data and health updates, but Nasa wasn't able to tell it to do anything while the antenna was offline.

Voyager 2

Voyager 2 is a 43-year-old space probe which was originally launched into space in 1977 with a mission to explore the outer planets of the solar system. The probe is one of a pair sent to investigate space.

Since its launch it has travelled billions of miles away from Earth and is outside the Sun's heliosphere - that's the protective bubble of particles and magnetic fields created by the Sun which surrounds the planets and the Kuiper Belt.

The spacecraft is now more than 11.6 billion miles (18.8 billion kilometres) from Earth.

It has since gone on to travel further than our solar system and continues to drift deeper into space than any of its creators originally thought it would be able to.

You've probably already seen the Voyager 2's work, it has taken some of the most famous and detailed images of Earth's neighbourhood as it passed Jupiter, Saturn, Uranus and Neptune.

Image source, NASA
Image caption,

This image of Saturn was taken by Voyager 2

Like its twin, Voyager 1, it carries on its journey a 'Golden Record'.

This disk contains recordings of sounds on Earth, information about humans and, most importantly, instructions on how to play it for any lucky aliens who find it.

Image source, NASA
Image caption,

Deep Space Station 43 is the only dish which can send commands to Voyager 2, it has been undergoing repairs since March

Major repairs

The repairs to Deep Space Station 43 are extensive and won't be completed until February 2021.

"What makes this task unique is that we're doing work at all levels of the antenna, from the pedestal at ground level all the way up to the feedcones at the centre of the dish that extend above the rim," said Brad Arnold, the DSN project manager at Nasa's Jet Propulsion Lab in Southern California.

"This test communication with Voyager 2 definitely tells us that things are on track with the work we're doing," he said.