Author: sreiny

Growing food is one of humanity’s most expansive and essential uses of the environment, and it’s something we can now track in great detail from satellites. From vast swaths of corn fields to smaller clusters of citrus groves, Landsat satellites help the U.S. Department of Agriculture (USDA) track what’s growing on America’s farmland. On a color-coded map, a patchwork of corn (yellow) and soybeans (green) span the Midwest, while a rainbow of crops cover California’s Central Valley.

Landsat, jointly managed by NASA and the U.S. Geological Survey, collects data-rich images of Earth’s land cover with a resolution that can detect individual farm fields. By combining Landsat data with information from other satellites and on-the-ground surveys, the USDA maps each crop and tabulates the acreages every year. The program started in 1997, grew to include all of the contiguous United States in 2009, and continues today.

The crop data helps officials evaluate damage from floods, droughts and other natural disasters, while resource managers can use it to direct crop rotation, study land-use change and monitor water use.

In 1968, humanity had its first look back at Earth from another world. Three astronauts on Apollo 8 orbiting the Moon peered out their capsule window and saw our home planet rising in the sky.

“We came all this way to explore the Moon, and the most important thing is that we discovered the Earth,” said William Anders, who snapped the iconic image that would become known as Earthrise.

Since NASA’s very beginning, we’ve kept a careful eye on Earth. From space, our view has shaped how humans see and understand our home. The Earthrise image, for example, helped inspire the first Earth Day 50 years ago. And our scientific observations from Earth orbit have shown how the planet is changing and point the way to solutions for environmental challenges around the globe.

Over the next 50 days leading up to Earth Day on April 22, we’ll bring you images and stories like this – some new, some familiar – every day to mark 50 years of celebrating our home planet.