At 10:02 a.m. Monday, if all goes as planned at Vandenberg Air Force Base, the latest generation Earth-observation satellite, Landsat Data Continuity Mission, a.k.a. Landsat 8, will get a boost into space atop an Atlas 5 rocket. Since 1972, seven satellites have documented Earth's continents and coastlines in images of telling and often astonishing detail. Forty years of Landsat data, what the government calls a "visible, long-term record of natural and human-induced changes on the global landscape," is archived and available online, free for anyone to use.
And it does get used. Water managers in California check Landsat data to help manage our share of that increasingly rare resource, right down to figuring out how to irrigate individual vineyards in the San Joaquin Valley. Wetlands researchers used the images to measure how much of the Gulf Coast Hurricane Katrina swallowed up. The data have tracked Amazon deforestation and, some say, have helped to slow it down.
These images aren't meant to be pretty pictures -- though many of them are. They don't set out to capture big moments and breaking news -- though they often do. They are, instead, a consistent accumulation of wide swaths of information over time, recording the surface of the whole Earth with instruments that see far beyond the human eye (in the infrared spectrum, for example) and the human point of view.
