Voyager at 40: Space exploration that just keeps on going

Forty years ago, Bob McDonald had the privilege of being at the Kennedy Space Centre for the launch of the most incredible space exploration mission of all time — the Voyager mission. It has been a groundbreaking 40 years of discovery ever since Voyager 1 and 2 launched in 1977. 

They were the first of our intrepid robotic explorers to fly by all four planets of the outer solar system: Jupiter, Saturn, Uranus and Neptune. They opened our eyes to the wonderful diversity of planets and moons around them, like never before. 

Today, at nearly 21-billion kilometres from Earth, Voyager 1 has travelled farther than any other human-made object ever. It's now hurtling through interstellar space. And Voyager 2 is not that far behind at 17-billion kilometres from Earth. 

• NASA - Voyager Mission Status

Despite these vast distances, both spacecraft still send updates to NASA on a daily basis. On the receiving end of those updates is the same project scientist who's been at the helm for the Voyager spacecraft mission since its inception, Dr. Ed Stone. 

Dr. Stone says we've already learned a lot about the nature of interstellar space from Voyager. 

"Although we're in interstellar space and we're not connected directly with the sun anymore, the sun can still launch a tsunami like waves, which take about 400 days to get out there. We didn't know that that would be the case, but that's what we're finding."

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