Galaxy  Evolution Explorer, or Galex, was placed in standby mode today as  engineers prepare to end mission operations, nearly nine years after the  telescope's launch. The spacecraft is scheduled to be decommissioned --  taken out of service -- later this year. The mission extensively mapped  large portions of the sky with sharp ultraviolet vision, cataloguing  millions of galaxies spanning 10 billion years of cosmic time.

The Galaxy  Evolution Explorer launched into space from a Pegasus XL rocket in April  of 2003. Since completing its prime mission in the fall of 2007, the  mission was extended to continue its census of stars and galaxies.

The mission's  science highlights include the discovery of a gigantic comet-like tail  behind a speeding star, rings of new stars around old galaxies, and  "teenager" galaxies, which help to explain how galaxies evolve. The  observatory also helped confirm the existence of the mysterious  substance or force known as dark energy, and even caught a black hole  devouring a star.

The California  Institute of Technology, Pasadena, Calif., leads the Galaxy Evolution  Explorer mission and is responsible for science operations and data  analysis. NASA's Jet Propulsion Laboratory, also in Pasadena, 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. Researchers sponsored by Yonsei University in  South Korea and the Centre National d'Etudes Spatiales (CNES) in France  collaborated on this mission. Caltech manages JPL for NASA.