The Fiber-Optic Broadband Optical Spectrograph
A Next-Generation Facility for Keck

With first-light in 2028, FOBOS will be the premier instrument for deep, high-target-density spectroscopy in the era of deep-imaging surveys, like the Vera C. Rubin Observatory Legacy Survey of Space and Time LSST, Euclid, and the Nancy Grace Roman Space Telescope. Its flexible acquisition system will position 1800 individual fibers or 45 fiber-bundles over Keck’s full 20-arcmin field-of-view, and provide spectroscopy covering the full optical band (0.31-1 μm) at moderate spectral resolution (R = 3500).