The past two years have been a little confusing for NASA’s Voyager 1 space probe, as its status as an interstellar traveller has been considered, debated, officially confirmed and then debated some more. However, new data looks to confirm that the intrepid spacecraft is actually in interstellar space, and the mission scientists have our Sun to thank for it.
Data from Voyager examining the wave provides further evidence the 37-year-old spacecraft has reached interstellar space. This region is filled with ionized gas, or plasma.
“Normally, interstellar space is like a quiet lake. But when our sun has a burst, it sends a shock wave outward that reaches Voyager about a year later. The wave causes the plasma surrounding the spacecraft to sing,” Ed Stone, project scientist on the mission since 1972, said.
Voyager has sent back signals to Earth that prove it has popped through our sun’s protective bubble and is now moving through the thicker plasma. Scientists can tell this is the case because the thicker plasma in interstellar space oscillates at a faster rate than less dense plasma and produces a different frequency when hit by the sun’s shock waves.
Voyager 1, whose mission was to study Jupiter and Saturn, is currently located about 11 billion miles from Earth and over 5 billion miles past Pluto. Still, Voyager is not quite out of our solar system, as it has one final ring of comets to penetrate before it can claim that distinction. It has Voyager 2 close on its heels, and scientists predict that it too will soon burst out of the heliosphere into interstellar space and continue sending data back about this heretofore-unexplored area.
The craft is eventually headed toward a close encounter with a star named AC + 79 3888, located 17.6 light years from the Earth. Arrival at that alien star system will happen in about 40,000 years.