Satellites measured land and ocean life from space as early as the 1970s. But it wasn't until the launch of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) in 1997 that the space agency began what is now a continuous, global view of both land and ocean life.
Twenty years of satellite data has helped scientists track phytoplankton populations in the ocean, study changing vegetation in the Arctic reaches of North America, monitor crop yields and more. Video credit: NASA's Goddard Space Flight Center.