Who gets to use the telescopes?
Half of the time is available to Caltech, one quarter to NASA/JPL (Jet Propulsion Lab), and one quarter to Cornell University. The observatory is owned and operated by Caltech, while the other institutions help with the finances and instruments. Specific users (usually astronomers or planetary scientists) are determined by each institution’s Telescope Allocation Committee (TAC), which meets twice a year. Astronomers apply to their local TAC, which decides 1) if the project is scientifically useful, 2) if the project is feasible, 3) if the project is a good use of the resources, and 4) if the time is available. Astronomers are assigned nights according to these priorities. Usually the 200-inch has 50% more hours requested than available (compared to 1000% on the Hubble Space Telescope) so there is some competition between astronomers. If weather is bad on your assigned night, tough luck! You have to reapply for more telescope time.
