Some of the earliest experiments in space environment interaction involved the study of wakes produced by the orbiting platform as it moved along its trajectory. The interaction of solid objects produces a wake in the anti-velocity direction. This wake is very pronounced in orbit because the orbital speed is supersonic relative to the ambient neutral and ion species. This type of interaction has occurred serendipitously ever since satellites were first placed in orbit, but recently a project has been initiated to perform organized wake experiments. In the last four years, the wake shield facility has been developed to be deployed from the space shuttle and to both measure and use the large reduction in particle densities produced by the structure.
The first flight of the wake shield facility was made in 1994 on the Space Transportation System (STS) 60 space shuttle flight. Unfortunately the shield could not be released from the shuttle's remote maneuvering system, so the facility was never clear of the shuttle's own contaminant cloud. However, it was possible to make studies of the modified space environment in the still existent wake and in the ram direction using the Charging Hazards and Wakes (CHAWS) experiment (Enloe et al., 1994), and compare the results to theoretical models of the charged particle environment (Davis et al., 1994).