The IBEX (Interstellar Boundary Explorer) is designed to figure out what happens at the boundary of the Solar System and how it helps preserve life here on Earth, and perhaps in other regions of the solar system. You may not know it, but the Sun’s Rays cause us to have a sphere around our Solar System which repels Galactic Cosmic Rays,  stopping them from entering the solar system. Basically this keeps us a little safer from deadly high energy particles which have the nasty effect of pulverizing DNA when they hit. The image below gives you some idea of what it looks like.

IBEX was launched about a year ago Oct 19th 2008.

IBEX Spacecraft

There are 3 boundaries. Terminal Shock,HelioPause, and Bow Shock.

The Voyager 1 satellite crossed the first of these, the Termination Shock (TS) on December 16th, 2004 at a distance of 94 AU.Maybe you will sleep a little easier when you consider the great lengths the universe is going through to protect you.

Sun Protects us from Cosmic Rays