For the first time in almost 30 years, a spacecraft managed to capture something astonishing: a hydrogen wall at the edge of the heliosphere. A new paper, which was recently published in Geophysical Research Letters, gives us an insight into a new discovery made by the New Horizons spacecraft. It seems that the space vehicle has observed ultraviolet light that, according to several physicists, comes from a hydrogen “wall” found at the edge of our solar system.
This is not the first time the hydrogen megastructure is seen, as it was first observed almost 30 years ago by the Voyager spacecraft. New Horizons had an almost decade-long trip from Earth, after which it became the first space vehicle to explore Pluto and its moons back in 2015.
The mysterious ultraviolet light
“Solar wind” is regularly being produced by the sun, which leads to the creation of a bubble around the solar system, known as heliosphere. This bubble extends around 10 billion miles from the sun. The main theory regarding the source of the ultraviolet light states that at the moment when neutral interstellar hydrogen atoms reach the heliosphere, they start to slow down, beginning to gather at the boundary of the sun’s influence. This is how the ultraviolet light is presumed to be created, due to the wall of hydrogen particles.
More evidence will be needed to support the theory
The Voyager spacecraft observed this phenomenon back in 1992. Since that moment in time, no other space vehicle has discovered this light until now. However, we cannot be sure yet if this theory is true. If a hydrogen wall is not the correct explanation for the existence of the ultraviolet light, then scientists will need to provide another theory as to why we can observe this light so far away from the sun. New exciting times are awaiting, as New Horizons will start searching for ultraviolet evidence of this hydrogen wall two times a year, starting with 2019.