CAPE CANAVERAL, Fla., May 1 -- NASA launched its sky-mapping satellite, the Galaxy Evolution Explorer, on Monday on a mission to map the ultraviolet universe. The Galaxy spacecraft is equipped with a telescope that records in the near- and far-ultraviolet range of the electromagnetic spectrum, a range that has not been extensively mapped in the past. The telescope is sensitive enough to pick up ultraviolet transmissions from galaxies 10 billion light-years away. The mission's ultraviolet detectors will hone in on galaxies containing young, hot, short-lived stars that emit a great deal of ultraviolet energy. Because these galaxies are actively creating stars, studying them will help scientists learn more about how, when and why stars form inside galaxies, NASA said. The 609-pound satellite was launched at 8 a.m. by a Pegasus XL rocket, from beneath a Stargazer jet about 100 miles east of Florida's Kennedy Space Center over the Atlantic Ocean. The mission will last for up to 28 months. The Galaxy Evolution Explorer mission is led by the California Institute of Technology, which is also responsible for science operations and data analysis. NASA's Jet Propulsion Laboratory, Pasadena, Calif., a division of Caltech, manages the mission and built the science instrument. The mission was developed under NASA's Explorers Program, managed by the Goddard Space Flight Center, Greenbelt, Md. Orbital Sciences Corp., Dulles, Va., is responsible for the spacecraft, integration and testing, ground data system and mission operations and the launch vehicle. Other partners include the University of California, Berkeley; as well as Johns Hopkins University, Baltimore, Md., and its Space Telescope Science Institute. Key flight optics components were developed and contributed by France's Laboratoire d'Astrophysique de Marseille. Test equipment and science operations software were developed and contributed by Yonsei University in Seoul, South Korea. For more information, visit: www.galex.caltech.edu