35 years after its launch, has Voyager 1 finally left the solar system? It’s not as clear-cut as you might think: cross Pluto’s orbit, the Kuiper Belt (where I guess Pluto technically belongs), and even the Oort Cloud (from where comets come), and you’re still not there.
Barriers still have to be crossed, essentially signals that its leaving the Sun’s bubble of charged particles. The problem is that we don’t know precisely where they are, but there are some telltale signs:
Two of three key signs of changes expected to occur at the boundary of interstellar space have changed faster than at any other time in the last seven years, according to new data from NASA’s Voyager 1 spacecraft.
For the last seven years, Voyager 1 has been exploring the outer layer of the bubble of charged particles the sun blows around itself. In one day, on July 28, data from Voyager 1’s cosmic ray instrument showed the level of high-energy cosmic rays originating from outside our solar system jumped by five percent. During the last half of that same day, the level of lower-energy particles originating from inside our solar system dropped by half. However, in three days, the levels had recovered to near their previous levels.
A third key sign is the direction of the magnetic field, and scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space.
No word on if it’s encountered Klingons yet. Not that they’d tell us anyway…