NASA's IBEX finds influence of galactic magnetic field extends beyond solar system

New research suggests that the enigmatic "ribbon" of energetic particles discovered at the edge of our solar system by NASA's Interstellar Boundary Explorer (IBEX) may be only a small sign of the vast influence of the galactic magnetic field.

IBEX researchers have sought answers about the ribbon since its discovery in 2009.

Comprising primarily space physicists, the IBEX team realized that the galactic magnetic field wrapped around our heliosphere-the giant "bubble" that envelops and protects our solar system-appears to determine the orientation of the ribbon and the placement of energetic particles measured in it.

An unlikely teaming of IBEX researchers with ultra-high-energy cosmic ray physicists, however, has produced complementary insights that dovetail with IBEX's studies to produce 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 cosmic ray physics team measured super-high-energy particles to study anisotropies, or the unequal distribution of particles as they arrive from various directions. The particles were expected to be isotropic, or equally distributed as they arrived from all directions. They are indeed seen to be fairly isotropic, but with some anisotropy in different directions.

"The teraelectronvolt (TeV) particles measured by the team are incredible," Dr. David McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute, said.

"Each one is up to 12 orders of magnitude more energetic than, for example, a photon of visible light coming from the Sun," he said.