‘zap pits’

Updated About encyclopedia.com content Print Article Share Article
views updated

‘zap pits’ (microcraters) Small craters, ranging in size from less than 1 μm to about 1 cm, on the exposed surfaces of lunar samples, caused by the hypervelocity impact of micrometeorites and dust particles with masses less than about 10−3 g; Typical craters consist of a glass-lined pit, a ‘halo’ zone of fractured material surrounding and underlying the pit, and a spalled zone concentric to the pit. This spallation may leave the glass-lined pit standing on a pedestal.