Cluster - Four ESA spacecraft orbiting the Earth to investigate the small-scale structure (in three dimensions) of the Earth's plasma environment. News, orbital position, mission overview and scientific resources.
Earth Observing System (EOS) - EOS is the centerpiece of NASA's Earth Science Enterprise (ESE). Includes a science component and a data system supporting a coordinated series of polar-orbiting and low inclination satellites for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans.
Explorer Spacecraft Series - Information and data listing the Explorer series of spacecraft (1958-1991).
