Voyager 2 sends update from beyond the solar system after 42 year mission

Nick Allen

A Nasa probe has sent back its first data from beyond the solar system after an incredible 42-year journey.

Voyager 2 blasted off in 1977 and left the heliosphere, the so-called "solar bubble" that envelops Earth and our neighbouring planets, last year.

It set off a month before its twin, Voyager 1 which made quicker time and became the first man-made object to leave the solar system in 2012.

Data from Voyager 2 has helped reveal the "blunt bullet" shape of the heliosphere around the solar system Credit: NASA

But one of the instruments on Voyager 1 was broken, and Voyager 2 was able to send back an even more detailed treasure trove of data from 11 billion miles away.

It found that the heliopause - the barrier where the solar and interstellar winds meet - was much more defined than scientists anticipated.

Voyager 2 took less than a day to cross the heliopause, whereas Voyager 1 had taken 80 days.

As it left the solar system Voyager 2 also recorded particles leaking out into interstellar space, whereas Voyager 1 had recorded elements of the interstellar wind coming the other way.

Comparison of where the two probes left the solar system helped to show the shape of the heliosphere.

Don Gurnett, astronomy professor at the University of Iowa, said: "There's almost a spherical front to this. It's like a blunt bullet."

Professor Edward Stone, of the California Institute of Technology, compared it to a supertanker moving through interstellar space.

He said: "There's a wave in front, just as with the bow of a ship. We are trying to understand the nature of the boundary where these two winds collide."

Both Voyager probes were only built to last 12 years.

They were initially sent to study the outer planets including Jupiter, Saturn, Uranus and Neptune, but then just kept on going.

The two probes will eventually cease to communicate over the next decade.

But Bill Kurth, of the University of Iowa, said: "They will outlast Earth. They are in their own orbits around the galaxy for five billion years or longer, and the probability of them running into anything is almost zero."

On board are drawings of a man and a woman, bird and whale songs, and a recording of "Johnny B. Goode" by Chuck Berry.