Metamorphism produced by hypervelocity impact between objects of substantial size moving at cosmic velocity (at least several kilometers per second). Kinetic energy is converted into seismic and heat energy almost instantaneously, yielding pressures and temperatures far in excess those in normal terrestrial metamorphism. On planetary bodies with no atmosphere, smaller impacting bodies (even micrometeorites) can produce shock metamorphicRocks that have recrystallized in a solid state due to changes in temperature, pressure, and chemical environment. Click on Term to Read More effects as observed in meteorites. Observed effects include planar deformation features (PDFs), diaplectic glassNatural glass formed by shock transformation from any of several minerals (more commonly feldspar) without melting. It is found in some meteorites and meteorite impact craters. Diaplectic plagioclase glass is called maskelynite and is found in martian shergottites. Click on Term to Read More, and melting. Effects are observed in different minerals at different pressures.