Twenty-five years of weather satellites.

Twenty-five years of weather satellites

This month marks the silver anniversary of weather watching from satellites. On the right, in the insert, is TIROS-1 (Television Infrared Observation Satellite), a 260-pound, polar-orbiting satellite that sent back the weather picture from space (also shown at right) on April 1, 1960. Before satellites, weather observations were unavailable for more than 80 percent of the planet. Today, a fleet of geostationary (hovering at a fixed point above the equator) and polar-orbiting (traveling from pole to pole) satellites-- including a more recent, 2,288-pound TIROS, which sent back the picture at left-- provides not only an almost continuous view of weather patterns all over the globe, but also a flood of other data including vegetation cover on land, oceanic and atmospheric temperatures and particle activity surrounding the earth.