First Light for the 4LGSF

Published: 02 May 2016
4LGSF and VLT UT4

First light for the Four Laser Guide Star Facility (4LGSF) was achieved on 26 April 2016 (see the Release). The four 22-watt laser beams excite sodium atoms in the upper atmosphere to provide four point sources for adaptive optics systems to compensate the atmospheric turbulence. 4LGSF is an integral part of the Adaptive Optics Facility (AOF), which includes a deformable secondary mirror (DSM) and the GALACSI and GRAAL modules. The complete facility will gradually be commissioned over the next year and a half.