HVI phenomena: Applications to space missions

Space Missions, by virtue of the energy required for geocentric or heliocentric orbits, generally explore and hence encounter objects at velocities in excess of terrestrial values for macroscopic objects. Their demand, to quantify impact relationships, extends from penetration to momentum exchange; from ionisation to plasma diagnostics. Response to the "need to know" in space and defence has led to the development of laboratory facilities and of hydrocodes; but because the parameter space of velocity and dimension in space cannot be replicated in full, the scaling of velocity and dimension is a vital element in establishing quantitative formula to decode space impact features. Such scaling - vital to generalised Formula for both astrophysical and engineering aspects of space research - is reviewed; hypervelocity impact products generated for cratering, marginal penetration, hole growth, impact momentum and ionisation charge and current in the space environment are presented.