Of the three telescopes carried by NASA's Swift satellite, only one captures cosmic light at energies similar to those seen by the human eye. Although small by the standards of ground-based
observatories1, Swift's Ultraviolet/Optical Telescope (UVOT) plays a critical role in rapidly
pinpointing2 the locations of gamma-ray bursts (GRBs), the brightest explosions in the
cosmos3. But as the
proxy4(代理) to the human eye aboard Swift, the UVOT takes some amazing pictures. The Swift team is celebrating eight years of UVOT operations by collecting more than 100 of the instrument's best snapshots in a web-based photo gallery (http://www.swift.psu.edu/uvot/coolPics.php). The images also can be viewed with the free Swift Explorer Mission iPhone app (https://itunes.apple.com/us/app/swift-explorer/id465669299?mt=8) developed by the Swift Mission Operations Center (MOC), which is located in State College, Pa., and operated by Penn State.
Swift has detected an average of about 90 GRBs a year since its launch in 2004. "When we aren't studying GRBs, we use the satellite's unique
capabilities5 to engage in other scientific
investigations6, some of which produce beautiful images from the UVOT that we're delighted to be able to share with the public," said Michael Siegel, the lead scientist on the UVOT and a research associate in astronomy and
astrophysics(天体物理学) at the MOC.
The targets range from comets and star clusters to supernova remnants, nearby
galaxies7 and active galaxies powered by supermassive black holes.
"One of our more challenging projects in the past was completing an ultraviolet
mosaic8 of M31, the famous Andromeda
galaxy9," said Stefan Immler, a member of the Swift team at NASA's Goddard Space Flight Center in Greenbelt, Md. "Because the galaxy is so much larger than the UVOT field of view, we had to take dozens of pictures and blend them together to show the whole object."