The Alfv¿n critical velocity mechanism for ionization of a neutral gas streaming across the magnetic field has been demonstrated in laboratory experiments. In March 1983, two rocket-borne experiments with Ba and Sr tested the effect in the wall-less laboratory of space from Punto Lobos, Peru, near 430 km altitude. ''Star of Lima used a conical Ba shaped charge aimed at an instrument payload about 2 km away. Because of rocket overperformance the detonation occurred in partial sunlight, so that less than 21.6% of the ionizing UV was present. As discussed in other papers in this series, particle and field measurements indicate the production of hot electrons and waves in the energy and frequency range respectively predicted to produce a cascade of ionization by the Alfv¿n mechanism. However, the ionization fluxes and wave energy density did not reach cascade levels, and optical observations indicate that only 2.5 to 5¿1020 Ba ions were produced. A substantial portion and perhaps all of the ionization could have been produced by solar UV. The failure of the Alfv¿n process in this experiment is not well understood.