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September 21, 2016

Toward a space-based perspective of our planet in the 1960s

Fifty years ago, on September 21, 1966, Secretary of the Interior Stewart Udall announced his vision to create “a program aimed at gathering facts about the natural resources of the earth from earth-orbiting satellites.”

Udall boldly revealed that NASA and the Interior Department would collaborate on Earth-observing space technology to monitor the planet’s natural resources. Initially called Project EROS, short for Earth Resources Observation Satellites, the many fruits of this ambitious vision would become unparalleled in remote sensing.

In the fall of 1966, NASA was nearly three years away from launching the Apollo 11 mission and planting man’s first footprint on the moon. Only limited time and effort had been spent exploring ideas for an Earth-observing satellite. Nevertheless, to ensure that sufficient attention would be brought to such a concept, U.S. Geological Survey Director William Pecora convinced Interior Secretary Stewart Udall to issue a press release on September 21 announcing Project EROS, later renamed the Landsat program.

Fifty years later to the day, the Department of the Interior and NASA are celebrating this farseeing vision with a special event featuring Secretary Udall’s son, Senator Tom Udall of New Mexico.

Landsat origins

In the 1950s, Bill Pecora had become aware, along with a few other agricultural scientists and other geologists, that aerial surveys of land surfaces could reveal features that were difficult, time-consuming, and expensive to trace on the ground. By the early 1960s the U.S. was flying both classified land-observation satellites plus the country’s first weather satellites.  NASA scientists and engineers had conducted some highly successful aircraft-based remote sensing projects, many of them conducted in cooperation with the USGS and U.S. Department of Agriculture.

Both Secretary Udall and Director Pecora understood the vast potential for the useful, versatile knowledge we could gain from land-imaging satellites – knowledge that could be used by the Department of the Interior to accomplish its mission, knowledge that could be used by institutions and scientists outside the government and beyond the United States.  


Stewart Lee Udall, U.S. Secretary of the Interior, 1961-69
Stewart Lee Udall, Secretary of the Interior, 1961-69. 


Landsat and Earth observation worldwide

Since the first ERTS 1 satellite (later Landsat) was launched by NASA in July 1972, successive satellites in the Landsat program have been imaging the landmasses of our planet. Landsat, a joint effort of USGS and NASA, has produced the longest, continuous record of Earth’s land surface as seen from space.

NASA launched the latest Landsat mission, Landsat 8, in February 2013. After a three-month testing period, the USGS assumed ownership and operations of the satellite. Landsat 8 works in tandem with the older USGS Landsat 7 satellite to provide data every eight days for any spot on the Earth’s land masses, supporting farmers, foresters, conservationists, water managers, and scientists around the globe.

A common vocabulary for change

The authoritative information gathered by multiple Earth observation satellites, such as Landsat, now serves as a common, reliable record for environmental change around the world. Indeed, in the last half century, the record of Earth observation from space has become the indispensable foundation of almost all deliberations about the state of the Earth. Secretary Udall’s vision has fundamentally remade how we see and understand our planet.

Learn more

Celebrating 50 Years of a Vision to Observe Earth for the Benefit of All
An Idea that Worked: an interview with Interior Secretary Stewart Udall
Landsat: Continuing to Improve Everyday Life (sample applications)
USGS Landsat
NASA Landsat
Canyonlands National Park, Landsat 8 image (download option)

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