Charging of a Man in the Wake of the Shuttle

摘要

Charging of the DMSP F6 and F7 satellites is shown to result from the combined effects of high flux of high energy auroral electrons and low ambient background ion density. POLAR computer code calculations are presented which show that a shuttle size object will charge more than 3000 volts negative under these charging conditions. The highly charged shuttle accelerates ions to the shuttle potential producing a high energy mono-energetic plasma environment near the shuttle. During these charging events, an astronaut performing EVA will charge with its ion collection orbit limited. Material secondary properties will produce differential charging on the astronaut of the same magnitude as the shuttle charging potential. NASCAP computer code calculations of EMU charging in the near shuttle environment show differential voltage of 2600 volts and overall charging 1000 volts more negative than the shuttle will occur.