Remote sensing is the discipline of acquiring and interpreting aerial images of the earth or other planets using sensor-based technology. Those images, covering subjects like the earth’s surface, the atmosphere, oceans, objects and phenomenon, are then analysed to provide precise data that would not be possible to obtain easily by other means. Dr Joseph Michalski, Associate Professor, Department of Earth Sciences at the University of Hong Kong, is a geologist and planetary scientist who uses remote sensing to study the mineralogy and geology of planets at HKU’s Planetary Mineralogy and Spectroscopy Laboratory.