NASA's Voyager 2 reaches interstellar space medium

  • NASA's Voyager 2 reaches interstellar space medium

NASA's Voyager 2 reaches interstellar space medium

NASA research on Voyager data, published as five separate studies in the journal Nature Astronomy, shows that the spacecraft has left the sun's bubble of magnetic fields and particles, far beyond the Oort Cloud.

"We didn't know how large the bubble was and we certainly didn't know that the spacecraft could live long enough to reach the edge of the bubble and enter interstellar space", said Prof Ed Stone, of the California Institute of Technology, who has been working on the mission since before its launch in 1977.

"There appear to be cosmic ray boundary layers on both sides of the heliopause, with the outer one only being evident at the position of Voyager 2", the researchers said, adding this external layer "was not evident at the place, time where Voyager 1 crossed". Now, the new measurements from Voyager 2 indicate that the boundaries between our solar system and interstellar space may not be as simple as once thought.

Shaped something like a windsock in a stiff breeze, the heliosphere is formed by the Sun's magnetic field and solar winds that can reach speeds of three million kilometres per hour. The NASA scientists were apprehensive at the outset of the journey whether it would survive to see this landmark of crossing the border of the solar system. Scientists say that the increased density of plasma is evidence that the vehicle is traveling out of the enclosure of warm and low-density plasma of solar winds into cold and high plasma density interstellar space. This is despite the fact that NASA scientists were not sure that he will be able to "survive" and overcome that boundary.

And then there's the leakage enigma. Many other important information is also being received in the direction of understanding the heliosphere from the equipment installed on Voyager-2.

"This is very odd", said Tom Krimigis, a scientist in the Applied Physics Laboratory at Johns Hopkins University and senior author of a study reporting on measurements of charged particles.

"We had no good quantitative idea of how big this bubble is", he commented.

The Sun's activity waxes and wanes in 11-year cycles.

"If an astronaut moves closer to the source [of cosmic rays], it is going to be important to understand how much intensity there is", Stone said. Now, there's a second spacecraft beyond the limits of our solar system: Voyager 2. "That says that these two points on the surface are nearly at the same distance", said Bill Kurth, a University of Iowa research scientist and a co-author of one of the studies. Even after that they will continue on their trajectories long after they fall silent. In addition to sending back data, the two little probes also carry with them The Golden Record: pictures, messages, and sounds from Earth. "They are in their own orbits around the galaxy for five billion years or longer, and the probability of them running into anything is nearly zero".