Researchers observed a "ribbon" of particles at the edge of our solar system that could help them gain insight into the larger influence of the galactic magnetic field.
The phenomenon was first discovered in 2009 by NASA's Interstellar Boundary Explorer (IBEX). The scientists found the galactic magnetic field that wraps all the way around the heliosphere (the "bubble" that protects our solar system" influences the orientation of the ribbon, a Southwest Research Institute news release reported.
The researchers looked into a "more complete picture of the interactions at the solar system boundary and how they reach much farther out into the space between the stars," the news release reported.
The team measured super-high-energy particles in hopes of learning more about anisotropies ("the unequal distribution of particles as they arrive from various directions"). The team found they were "fairly isotropic" but they did observe low levels of anisotropy in different directions.
"The teraelectronvolt (TeV) particles measured by the team are incredible," Doctor David McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute said in the news release. "Each one is up to 12 orders of magnitude more energetic than, for example, a photon of visible light coming from the Sun. To illustrate this scale, consider that $1 raised 12 orders of magnitude is...a trillion dollars. These are super-high-energy cosmic rays made in some of the highest energy acceleration mechanisms that exist in the galaxy, such as supernovae."
The amount of anisotropy is very small, but not insignificant. Researchers believe it is influenced by the galactic field; the finding suggests the magnetic field reaches farther out into the galaxy than researchers previously believed. When the high-energy particles move in from the outer realms of the galaxy they are influenced by the magnetic field, which causes anisotropy to occur.
