NASA Galaxy Evolution Explorer Mission Comes to the End

NASA’s Galaxy Evolution Explorer, or Galex, was placed in standby mode as engineers prepare to end mission operations, nearly nine years after the telescope’s launch. The spacecraft is scheduled to be decommissioned. The Galaxy Evolution Explorer was launched on April 28, 2003. Its mission is to study the shape, brightness, size and distance of galaxies across 10 billion years of cosmic history. The 50 centimeter diameter (19.7-inch) telescope onboard the Galaxy Evolution Explorer sweeps the skies in search of ultraviolet-light sources. Ultraviolet is light from the higher end of the electromagnetic spectrum, just above visible light in frequency, but below X-rays and gamma rays. While a small amount of ultraviolet penetrates Earth’s atmosphere, causing sunburn, the Galaxy Evolution Explorer observes those ultraviolet frequencies that can only be seen from space. 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.