NASA's Galaxy Evolution Explorer. or GALEX. is an orbiting space telescope observing
galaxies in ultraviolet light across 10 billion years of cosmic history.
GALEX's observations are telling scientists how galaxies. the basic structures of our Universe. evolve and change.
A Pegasus XL rocket launched GALEX into orbit off NASA Kennedy Space Center's central Florida coastline on April 28th. 2003.
Although originally planned as a 29-month mission. the mission lifetime was extended.
and GALEX continues to provide data and insight.
In fact. GALEX played a critical role in providing data for a five-year survey of 200.000 galaxies. stretching back seven
billion years in cosmic time. confirming that dark energy is driving our universe apart at accelerating speeds.