Published online by Cambridge University Press: 02 August 2016
The stellar intensity interferometer at Narrabri Observatory was operated for ten years. Measurements were made of 32 single stars of spectral type 0 to F and were used to establish the first completely empirical temperature scale for hot stars. The application of a high-resolution interferometer to stellar astronomy was explored: observations were made of binary, rotating and emission-line stars, limb-darkening, polarized light and of the effects of atmospheric scintillation and of Cerenkov radiation from the night sky. This programme was completed in 1973. An analysis has been made of the astronomical programme and value to stellar astronomy of a much larger and more sensitive instrument. An intensity interferometer capable of reaching stars of magnitude +7.3 with a baseline of 2 km has been designed and its cost has been estimated.