Voyager Nears Edge of Interstellar Space

Scientists this week say the Voyager 1 space probe, launched in 1977, has reached the end of our solar system after going through an area known as "termination shock" and is entering the heliosheath.

The termination shock is a region where the solar winds from the sun slow abruptly from a speed of up to 1.5 million miles per hour due to pressure from gas between the stars. The exact location of this region is unknown since it can expand or contract based on the pressure of the solar wind.

"The consensus of the team now is that Voyager 1, at 8.7 billion miles from the Sun, has at last entered the heliosheath, the region beyond the termination shock," said Dr. John Richardson from MIT, Principal Investigator of the Voyager plasma science investigation.

Voyager 1 first observed magnetic field strength increasing by a factor of two and a half in December 2004, which is expected when solar wind slows down. From December until now, the field stengh remained at these high levels.

"Voyager's observations over the past few years show that the termination shock is far more complicated than anyone thought," said Dr. Eric Christian, Discipline Scientist for the Sun-Solar System Connection research program at NASA.

After completing it's original mission of exploring Jupiter and Saturn, Voyager 1 and its twin probe Voyager 2 are now being used to explore the outermost regions of the solar system.

It is quite possible that before the probes go dark sometime around 2020, humans may have their first glimpses into interstellar space.