The amount of water contained in the top few centimeters of soil is small on a global scale, but it is critical for agriculture analysts trying to monitor commodity production and humanitarian need.
NASA's newest Earth-observing satellite soars into space aboard a Delta II rocket, tasked with improving weather forecasts and continuing long-term climate records.
Landsat 7, NASA's newest Earth-observing satellite, launched without a hitch on April 15, 1999, at 2:32 p.m. EST from Vandenberg Air Force Base, California.
Approximately 19,000 manmade objects larger than 10 centimeters orbit the Earth. These images, based on models, show the distribution of orbital debris around Earth.