Probe to map solar system’s edge

? A small NASA spacecraft embarks on a two-year mission this weekend to give scientists their first view of the happenings at the edge of the solar system.

The Ibex probe, short for Interstellar Boundary Explorer, will study a chaotic region in space where the solar wind from the sun clashes with cold gases from interstellar space.

The solar wind, a stream of charged particles spewing from the sun at 1 million miles per hour, carves out a protective bubble around the solar system. This bubble known as the heliosphere shields against most dangerous cosmic radiation that would otherwise interfere with human spaceflight.

Scientists recently discovered that the solar wind pressure is at its weakest level in 50 years, although the exact reason remains a mystery. Ibex could help confirm whether the heliosphere is shrinking.

Observations from Ibex should help researchers in “unlocking the secrets of this important interaction between the sun and the galaxy,” said David McComas of the Southwest Research Institute in San Antonio.