To facilitate new research and enhance existing data regarding the interaction of dynamic geophysical systems, NASA is in the process of developing a comprehensive Earth Observing System (EOS). A multi-component program, one of the unifying aims of EOS units is to measure the impact of human activities on Earth's geological and atmospheric processes.

The first component in the EOS array of remote sensing instruments is the Terra satellite, launched into a near-circular, sun-synchronous Earth orbit in December, 1999.

The development of NASA's EOS (a part of NASA's Earth Sciences Enterprise [ESE]) will result in a group of satellites—each designed for a specific research purpose— that together will feed data to the Earth Observing System Data and Information System (EOSDIS) network that will make the information available to research groups around the world. As of April 2002, three...