[Source: Kasha Patel, NASA’s Goddard Space Flight Center] Landsat satellites have monitored Earth’s environment for more than four decades, providing detailed imagery of some of our planet’s most precious ecosystems such as forests, coastlines, glaciers, volcanoes and oceans. Scientists, researchers, foresters, emergency responders and educators use the data sets to understand natural and human-caused surface changes, identify the ecological impact of natural disasters, examine the effectiveness of environmental policies, and help preserve our planet for future generations.
This Earth Day, NASA and the U.S. Geological Survey celebrates the environment by looking back at some of the impressive data sets from Landsat, a joint mission of NASA and U.S. Geological Survey. Through these Earth images and others, scientists can monitor the place that over seven billion people call home. + more

Further Reading:
+ Environmental Watch with Landsat satellites