The Space Probe New Horizons noticed ultraviolet glow, which seems to comes from behind the edge of the solar system. This glow can come from a wall of hydrogen, which occurs at the time when the influence of the sun becomes the maximum possible.
Even before the New Horizons flew by Pluto in 2015, the space probe scanned the sky with an ultraviolet telescope. With it, scientists hoped to detect signs of the hydrogen wall. As the sun moves along the galaxy, it produces a constant flow of charged particles, called the solar wind. It is he who infuses the «bubble» around the solar system, called Heliosphere.
Right behind the edge of this bubble, approximately 100 times further from the Sun than the earth, uncharged hydrogen atoms in the interstellar space have the opportunity to slow down when a collision with solar wind particles. Accordingly, the phenomenon of the so-called wall must dispel ultraviolet light.
It is known that two Voyager ships saw signs of such scattering of light 30 years ago.
«New horizons» is the first spacecraft who had the honor to double-check the observations of the precursors. He scanned ultraviolet radiation seven times from 2007 to 2017. During the flight of the spacecraft, it changed in accordance with the observations of the decade ago. All space ships saw more ultraviolet light further from the Sun, than expected. However, despite the confidence that this phenomenon is actually an effect confirming the existence of the wall, the team warns that the light can also come from an unknown source, which is further in the galaxy.
After the New Horizons will fulfill all missions in the solar system in 2019, it will continue to search for the wall. Tests will be held about twice a year. Presumably for 10-15 years.
And while some furrow spaces of space, others are focused on the close purposes: