NASA interplanetary probe "Voyager 1", launched 35 years ago, crossed the border into the heliosphere and became the first man-made object, left the solar system, U.S. researchers write in a paper accepted for publication in the journal Geophysical Research Letters.
"It seems that the" Voyager 1 "left the region, which is dependent on exposure to the sun, the data show such characteristics of hydrogen and helium, which are expected to be observed in the interstellar medium" — written by Bill Webber of the University of New Mexico and his colleagues.
The boundary of the solar system is the so-called the heliosphere — the "bubble" filled with the solar wind. Beyond it begins interstellar space, the property is no longer independent of the magnetic field, or from a stream of charged particles emanating from the sun.
According to scientists, August 25, 2012 probe, which was at that time at a distance of 121.7 astronomical unit (average radii of the earth's orbit) from the Sun, "felt" a sudden change in the flow of cosmic rays of different origin. Within a few days the flow of protons and alpha particles with energies of 1.9-2.7 MeV coming from the sun, declined by about 300-500 times. The intensity of galactic cosmic rays has doubled.
"Within a few days, the intensity of the heliospheric radiation decreased, and the intensity of cosmic rays increased, which we expect to happen in the near region of interstellar space," — says Webber was quoted as saying in a statement of the American Geophysical Union (AGU).