… and probably has been there for months, but new research is confirming the nature of this very interesting phenomenon. It is the outer edge of our solar system, where fast moving stuff heading away from the sun has slowed down because it’s movement is stifled by gravity, but some extra-energetic particles are still leaking out into the greater galactic region, from which they are unlikely to return. Also, the solar system’s magnetic fluxy stuff is bunched up in this region.
The cool thing about this is that we don’t really know exactly what is happening. Enough is known about the solar system, the sun, magnetics, plasma and particles, and stuff to have a reasonable model of what Voyager 1 will encounter, but the details remain quite vague.
“Voyager tells us now that we’re in a stagnation region in the outermost layer of the bubble around our solar system,” said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. “Voyager is showing that what is outside is pushing back. We shouldn’t have long to wait to find out what the space between stars is really like.”
Although Voyager 1 is about 11 billion miles (18 billion kilometers) from the sun, it is not yet in interstellar space. In the latest data, the direction of the magnetic field lines has not changed, indicating Voyager is still within the heliosphere, the bubble of charged particles the sun blows around itself. The data do not reveal exactly when Voyager 1 will make it past the edge of the solar atmosphere into interstellar space, but suggest it will be in a few months to a few years.
Scientists previously reported the outward speed of the solar wind had diminished to zero in April 2010, marking the start of the new region. Mission managers rolled the spacecraft several times this spring and summer to help scientists discern whether the solar wind was blowing strongly in another direction. It was not. Voyager 1 is plying the celestial seas in a region similar to Earth’s doldrums, where there is very little wind.