Earth's Vital Signs
NASA launched the Earth Observing System's flagship satellite "Terra," named for Earth, on December 18, 1999. Terra has been collecting data about Earth's changing climate. On February 24, 2000, sensors on NASA's Terra satellite began opening their shutters and making their first observations. The mission ushered in a decade of observations from NASA's Earth Observing System, a coordinated series of satellites that monitor how Earth is changing.
This image is based largely on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) — a sensor aboard the Terra Satellite — on July 11, 2005. Small gaps in MODIS’ coverage between overpasses, as well as Antarctica (which is in polar darkness in July), have been filled in using GOES weather satellites and the latest version of the NASA Blue Marble.