| Keck's existing laser guide star systems rely on a 13W pulsed dye laser to excite sodium atoms 90 km above the Hawaiian observatory. The upgraded system will feature a 20W continuous-wave solid-state laser based on a frequency-doubled Raman fiber amplifier. This long-exposure photo, courtesy of W. M . Keck Observatory/Andrew Cooper, shows lasers for guide stars fired from the Keck I, Keck II and Subaru telescopes, as well as the light from a car driving down the summit road next to the observatory. |
