The NASA spacecraft New Horizons has discovered the potential hydrogen wall in the outer reaches of our solar system.
The hydrogen wall is a region of space where our solar wind bubble ends or begins to interact with interstellar medium. When the interstellar medium pushes the bubble-like space inward, a boundary is created where interstellar hydrogen builds up. The visible boundary, which extends far beyond the orbit of Pluto, was first discovered in 1992 by the two Voyager spaceships that moved through interstellar space and the heliosphere. Now, 30 years later, NASA's New Horizons mission confirms the presence of hydrogen walls at the edge of our solar system.
Our sun sets charged particles outward and causes hydrogen in the space between planets to emit characteristic ultraviolet light. In August, New Horizons noted an added brilliance of this ultraviolet emission with Alice's instrument.
"This extra brightness is a possible signature of the hydrogen wall in the heliopause or a more distant background, and ongoing observations are planned with a cadence of about twice a year." Authors wrote in the study.
As New Horizons moves away from the Sun and approaches the edge of the Solar System, the observations made with his Alice instrument become more accurate and reliable.
"We assume that there is something special out there, an extra source of light, and if we get a chance with New Horizons, we might be able to imagine that." Study author Randy Gladstone of the Southwest Research Institute told Gizmodo:
The NASA spacecraft New Horizons is heading for a small Kuiper Belt object (KBO) called the 201