interstellar

Lost galactic hitchhikers can now rejoice when they visit our corner of the Milky Way. A new sky map created by a NASA spacecraft shows the boundaries of our solar system in comparison to the rest of the interstellar neighborhood.

The boundaries are defined by our sun's heliosphere -- a protective bubble created by the solar wind that travels outward and collides with incoming interstellar radiation. That typically invisible boundary became visible through energetic neutral atoms created in the region that speed toward the sun at velocities ranging up to 2.4 million mph.