Longest-running continuous view of Earth from space turns 40

It was exactly 40 years ago today when the first Landsat satellite—the ERTS-1—was launched into orbit by NASA to provide global coverage of large-scale human activity like building cities and farming over the long term. The very first Landsat satellite was sent into orbit on July 23, 1972 from Vandenberg Air Force Base in California and marks the world's longest-running Earth observation satellite program.

The images taken by Landsats are analyzed from different points along the visible and invisible light spectrum, which contain enough data to accurately detail the quality of large areas of farming land, grassland or forests. According to NASA Administrator Charles Bolden, Landsat satellites have been able to provide us with a critical perspective of the world, including how it's changed over the past four decades and how it continues to change.

The most recent Landsat that was sent into orbit was Landsat 7 in1999. The next generation Landsat Data Continuity Mission satellite (LDCM) is scheduled to be launched next year, and features the most recent thermal infrared sensors and imaging equipment, making it a much more advanced orbiting observatory that will join the rest of the Landsat family currently in space.

[via Space Ref]