The Voyager 2 mission released its first scientific measurements on interstellar space, according to recently published studies.
Voyager 2 underwent heliopause last November, joining Voyager 1 as the only human-made object to leave the heliosphere, the area around the sun that is affected by the solar wind . Fortunately, Voyager 2's instruments worked well enough to measure the particles and magnetic fields present in this distant region. Although its transition shares similarities with Voyager 1's 1945, these initial results reveal an unnoticed area of interaction between particles of space and particles of the sun.
Voyager probes, launched in 1
The broken plasma instrument of Voyager 1 made it difficult for scientists to directly assess whether and when the probe underwent heliopause in August 2012, and could not see the expected transition from hot plasma to hot plasma. the coldest and thicker plasma of the interstellar medium. Ultimately, measurements of the behavior of local electrons and magnetic fields confirmed that he had crossed the boundary .
Voyager 2 intersected last year with a working plasma instrument confirming past measurements and offering a first direct view of the transition, including a 20-fold -fold increase in plasma density, according to one paper published today in Nature Astronomy. The density is similar to the plasma density inferred by Voyager 1 scientists, with small discrepancies probably because of their differences in location.
T it has two heliopause intersections of probes at similar distances from the Sun: For Voyager 1, it was at 121.6 astronomical units, and for Voyager 2 it is 119 astronomical units (one AC is (1C). equal to the average distance from Earth to the Sun) . That the plasma density changes at such a distance, although the probes are more than 150 astronomical units except tells scientists that heliopause does not change much between these two radically different parts of the sky, the plasma physicist Bill Kurt tells Gizmodo. Kurt is one of the authors of the study and a scientist with the Voyager missions.
But many things are different between probes. Voyager 2 detected a continuous change in the direction of the magnetic fields as it underwent heliopause until Voyager 1 saw a change . Both missions saw a sharp increase in the number of high-energy cosmic rays, but Voyager 2 continued to see particles with lower energy than the Sun . Voyager scientists publish their results in five reports published today in Nature Astronomy ( 1 2 3 4 5 ) .
These types of measurements may be small in weeds, but they are crucial to understanding astronomers about space more generally; each star is assumed to have a similar boundary region between its sphere of influence and the local interstellar environment.
Voyager probes are outdated. Talks are already underway on how to distribute their remaining power writes R. Du Toit Strauss, Senior Lecturer at Northwestern University in South Africa, in a commentary on nature . Researchers still hope to better understand the deeper depths of the interstellar environment beyond regions where solar particles still flow from the heliosphere. They also hope to better understand the shape of the heliopause – the structure should have a long tail, such as a comet, but no evidence has yet been found for that tail.
Meanwhile, scientists will breastfeed the probes for all they deserve. There will be no alternative to taking data on this cosmos for a very long time – even if a new probe were launched today, the edge of the solar system will lie for decades.