NASA approves construction of satellite to scan galaxies

After eight years of study, NASA has approved the construction of an unmanned satellite that will scan the entire sky in infrared light to reveal nearby cool stars, planetary "construction zones" and the brightest galaxies in the universe. Launch of the Wide-field Infrared Survey Explorer (WISE) -- the second phase of the WISE mission -- is scheduled for late 2009. The satellite will orbit the Earth and operate for at least seven months, with data expected a few times a day.