Tom Friedmann checks out a sample diamond-like carbon film he created for the low-energy sensor (IBEX-Lo) on board NASA's Interstellar Boundary Explorer (IBEX). Diamond-like carbon films created at Sandia are helping probe the far boundaries of the solar system as part of a NASA mission to study how the sun?s solar wind interacts with the interstellar medium ? the matter that exists between the stars within a galaxy. IBEX?s two bucket-sized sensors, covering high and low energy ranges, are designed to capture particles bouncing back toward Earth from the distant boundary between the hot wind from the sun and the cold wall of interstellar space.