Voyager at the Edge: Cosmic Roadtrip Hits Milestone

After a 35 year odyssey the plucky little spacecraft Voyager 1 may be zipping through the final boundary that separates our solar system from Interstellar space – the space between the stars, according NASA.

Sailing through the outermost reaches of the solar system, mission scientists believe they have detected the telltale signs of Voyager crossing into a new region that represents the final boundary layer before officially leaving the Sun’s realm. Over the past year the intrepid probe has seen the levels of cosmic rays pouring in from the Milky Way galaxy skyrocket, while particles flowing out our solar system drop , indicating it is about to make its exit into the final frontier.

Scientists have dubbed this new region where Voyager is now traveling as the ‘magnetic highway’ because of the connection between the solar and interstellar magnetic lines and flow of charged particles in and out of the solar system.

“Although Voyager 1 still is inside the sun’s environment, we now can taste what it’s like on the outside because the particles are zipping in and out on this magnetic highway,” long-time Voyager scientist Edward Stone, based at California Institute of Technology, Pasedena, California said in a press release.

“We believe this is the last leg of our journey to interstellar space,” he added.

Launched in 1977, the twin Voyager spacecraft completed a grand tour of the outer planets back in the 80’s, swinging by all the gas giants: Jupiter, Saturn, Uranus and Neptune. Voyager 1 is currently the most distant object humankind has sent out into space having clocked about 11 billion miles (18.5 billion km), while Voyager 2 is now at the 9 billion miles (15 billion km) mark. It’s amazing to think that the weak signal from Voyager 1 takes approximately 17 hours to travel to Earth.

So Voyager is at last dipping its toes into the interstellar waters but hasn’t taken the plunge just yet. The team believes that it is still within the solar bubble – or heliosphere- – because the magnetic lines emanating from the Sun have not changed direction.

The big question now is exactly when it will it ‘officially’ cross the solar border and enter interstellar space. NASA scientists have been talking for months about Voyager being very close to leaving the Sun’s influence behind– but the fact is ,this is completely unexplored territory and no one knows for sure.

“Our best guess is that it’s likely just a few months up to a couple of years away,” Stone explained.

“The new region isn’t what we expected, but we’ve come to expect the unexpected from Voyager.”

The hope now is that Voyager reaches interstellar space before its power runs out- which is expected to happen around the year 2020.

Changing Planet

Meet the Author
Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.