Fast photometry of the Crab, SN 1987A and Aussat.

The appearance of SN 1987A led to the implementation of a fast sampling option in the data collection system of the photometer on the University of Tasmania's optical telescope. This option permits acquisition of continuous data trains of over one hour's duration at sample rates of 5 kHz. Monitoring of SN 1987A at regular intervals has permitted upper limits to be assigned to any pulsed fraction of the optical flux. Successful test observations of the Crab pulsar have been obtained, as well as observations of the geostationary Aussat satellites during their biannual specular-reflection episodes. For the latter, very accurate spin rates (about Hz) are determinable in short data runs because of the higher frequency components (about 100 Hz) in their light curves. These components are produced by the rows of solar cells on the outer surfaces of the satellites, and fast-Fourier transform analyses essentially permit the numbers of rows of cells to be counted precisely.