Interested in extrasolar planets? NASA's Kepler mission is set to launch this Friday, March 6 (in a few days!), which will be able to detect hundreds of Earth-size and smaller planets near the habitable zone. Kepler will search for planets using the transit method by measuring very small dips in the parent star's brightness (usually less than 1%!). A transit occurs when a star's planet crosses in front of the star, kind of like a mini-eclipse. When it transits, the star will dim ever so slightly.

Learn more here: http://kepler.nasa.gov/