Nasa confirms Voyager 1 probe has LEFT the solar system..Solar system “exit” debated
Thirty-five years after its launch, Voyager 1 has left the solar system.
Researchers say drastic changes in radiation levels measured by the probe confirm it has travelled beyond the influence of the Sun.
Mission scientists today confirmed the probe is ‘in a new region’ - although scientists are continuing to debate whether Voyager 1 has reached interstellar space or entered a separate, undefined region beyond the solar system.
The results confirm the probe has left the heliosphere.
The heliosphere is a region of space dominated by the Sun and its wind of energetic particles, and which is thought to be enclosed, bubble-like, in the surrounding interstellar medium of gas and dust that pervades the Milky Way galaxy.
On August 25, 2012, NASA’s Voyager 1 spacecraft measured drastic changes in radiation levels, more than 11 billion miles from the Sun.
Anomalous cosmic rays, which are cosmic rays trapped in the outer heliosphere, all but vanished, dropping to less than 1 percent of previous amounts.
At the same time, galactic cosmic rays – cosmic radiation from outside of the solar system – spiked to levels not seen since Voyager’s launch, with intensities as much as twice previous levels.
The findings have been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union.
‘Within just a few days, the heliospheric intensity of trapped radiation decreased, and the cosmic ray intensity went up as you would expect if it exited the heliosphere,’ said Bill Webber, professor emeritus of astronomy at New Mexico State University in Las Cruces.
He calls this transition boundary the ‘heliocliff.’
In the article, the authors state: ‘It appears that [Voyager 1] has exited the main solar modulation region, revealing [hydrogen] and [helium] spectra characteristic of those to be expected in the local interstellar medium.’
The possibility that the Voyager-1 spacecraft may have left the Solar System is being hotly debated.
Launched in September 1977, the probe was sent initially to study the outer planets, but then just kept on going.
Researchers studying its data say the craft appears now to be in a realm of space beyond the influence of our Sun.
But the US space agency (Nasa), which manages Voyager, says that it regards the probe as still being inside the Solar System.
The mission is currently moving more than 18 billion km from Earth, or 123 times the distance between our planet and the Sun.
Nasa funded the study but said any assessment that Voyager might be in interstellar space did not reflect the view of everyone working on the project, and Prof Weber acknowledges there is an ongoing debate about the probe’s status.
Many researchers would like a long period with the data all pointing in one direction before calling the exit definitive.
has it or hasnt it?
how much money is involved for further funding if it has?
how can they be sure what they have no idea of?..how can they know definitely what has occurred when they have nothing to test against?