In the ongoing debate over whether Voyager 1 has actually exited the solar system by bursting through the outer, amorphous magnetic border of what’s known as the heliosphere, a new study is out stating that it has already happened.
For years scientists have been assuming a certain magnetic signature when the big bust-out occurred. But new information that has piqued the interest even of skeptics indicates that the current debate may be anticlimactic: Voyager may have been cruising along in interstellar space for just over a year.
"It's a somewhat controversial view, but we think Voyager has finally left the solar system, and is truly beginning its travels through the Milky Way," said Marc Swisdak, a research scientist at the University of Maryland and the lead author of a paper published online in The Astrophysical Journal Letters, in a statement.
The confusion lies in the fact that we don’t really know what signals the spacecraft will send back once the momentous event has happened—a symptom of the very lack of information that sent us trolling interstellar space in the first place.
“The Voyager 1 spacecraft is exploring a region no spacecraft has ever been to before,” said Ed Stone, NASA's Voyager project scientist and a researcher at the California Institute of Technology in Pasadena, in a statement. “We will continue to look for any further developments over the coming months and years as Voyager explores an uncharted frontier."
The new model used indications that Voyager 1 had been detecting interstellar magnetism for the past year as a sign that it had exited the solar system on July 27, 2012. It takes into account the possibility that the currents of magnetic lines in interstellar space can travel in the same direction as those in the heliosphere, which means that the border between the two is not as defined as previous models have assumed.
The model that researchers have been using—and have not let go of yet pending further evaluation—looks for another type of signature.
“Other models envision the interstellar magnetic field draped around our solar bubble and predict that the direction of the interstellar magnetic field is different from the solar magnetic field inside,” Stone said. “By that interpretation, Voyager 1 would still be inside our solar bubble.”
What is not in dispute is that Voyagers 1 and 2 have traveled farther from Earth than any man-made object ever has. And it’s just a matter of time before Voyager 1, which is currently 11 billion miles away, finishes passing through this border region once and for all.
Meanwhile, NASA is contemplating the new study’s perspective on the data that has been coming in from the probe, Stone said.
“The fine-scale magnetic connection model will become part of the discussion,” he promised.