1. Institute of Space and Astronautical Sciences, Tokyo, Japan
2. Electrotechnical Laboratory, Tokyo, Japan
3. National Institute of Polar Research, Tokyo, Japan
4. Marshall Space Flight Center, Huntsville, Alabama 35812
5. Southwest Research Institute, San Antonio, Texas 78284
6. TRW, Los Angeles, California 90278
7. Stanford University, Stanford, California 94305
8. Johnson Space Center, Houston, Texas 77058