The U.S. National Aeronautics and Space Administration (NASA) initiated the Mission to Planet Earth (MTPE) to serve as a pivotal part of the U.S. Global Change Research Program (USGCRP). The role of MTPE is to use space- and ground-based measurement systems to provide the scientific basis for understanding global change. As described in the chapter "Earth Observing System," of NASA's (1993) Earth Observing System (EOS) Reference Handbook the centerpiece of MTPE is the Earth Observing System (EOS), a constellation of satellites designed to provide global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans. EOS is scheduled to commence in the late 1990s and continue for at least 15 years.
NASA's EOS Reference Handbook explains development of the EOS Program and its rationale in the chapters "EOS Program Chronology" and "EOS Science Objectives," respectively. EOS Acronyms explains the many acronyms used in the handbook. The chapter "International Cooperation" describes coordination of NASA's EOS activities with the space-based Earth observation plans of Europe, Japan, and Canada to form the basis for a comprehensive International Earth Observing System (IEOS). NASA's EOS Program also benefits from and complements the capabilities and needs of other U.S. Federal Government agencies, as described in the chapter "Interagency Coordination."