Interferometric measurements of atmospheric seeing

In conjunction with the Stellar Interferometer project at Sydney University, a shearing interferometer system has been constructed to measure the atmospheric "seeing" in real time using a portable telescope. The interferometric method allows direct measurement of the parameter r₀, which derives from the theory of atmospheric turbulence. This permits reliable comparison with "seeing" determinations by other methods. This paper briefly describes the instrument and presents initial results of the observing program.