Interferometry and the Development of NPOI

Lowell Observatory is a partner in the The Navy Precision Optical Interferometer (NPOI) facility, a long-baseline optical interferometer (LBOI) located at Lowell's Anderson Mesa site near Flagstaff, AZ. NPOI is a modern realization of LBOI efforts, which began in 1919 with the 20-foot beam interferometer that Michelson and Pease bolted to the 100-inch Hooker Telescope. The ensuing colorful century of LBOI, replete with trials and tribulations, visionary and eccentric leaders, and most of all, scientific achievements, is reviewed with an eye towards the promising future of the technique.