Lunar Occultations: From Past to Future Achievements

Abstract

For several decades, lunar occultations have represented a powerful and productive technique for high angular resolution investigations of a broad class of astronomical sources: from stellar angular diameters to close binaries, from circumstellar shells to the Galactic Centre.The resolution and sensitivity offered by lunar occultations still compare favorably with the capabilities of other more modern methods in the optical and near-infrared. A remarkable fact, when one considers that during the past 20 years practically nothing or very little has changed in the way we observe lunar occultations: a sharp contrast with the impressive technological and scientific advancements of other techniques.The novel possibility of using small areas of fast-readout, low-noise array detectors to record lunar occultations, however, is about to bring radical improvements. We discuss the impact of such detectors on the efficiency of observation and the gain for what concerns the resolution and sensitivity of lunar occultations measurements. New applications such as wavelength-resolved observations and investigations of low-contrast extended sources appear particularly interesting.