EOS (Earth Observing System) is a series of polar-orbiting and low-inclination satellites for conducting long-term global observations of Earth's land surface, atmosphere, oceans, and biosphere. EOS is the centerpiece of NASA's Earth Science Enterprise program (formerly called Mission to Planet Earth), and together with other missions from NOAA (National Oceanic and Atmospheric Administration), Europe, and Japan forms the comprehensive International Earth Observing System (IEOS). Current and future EOS missions include:

· SeaStar/SeaWiFS
· TRMM
· Landsat-7
· QuikScat
· Terra (EOS AM-1)
· ACRIMSAT
· EO-1
· SAGE III
· Jason-1
· Aqua (EOS PM-1)
· ICESat (EOS Laser Alt-1)
· ADEOS-2
· SORCE
· Aura (EOS Chem)