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In other words, why did it take so long for a Landsat ground station to be added at EROS? The answer to that question involves the expectations for EROS and the twists and turns of history.

Setting Expectations

The idea of an Earth-observing satellite to monitor land change gained ground after Interior Secretary Stewart Udall announced the EROS program via press release in 1966. Even when NASA agreed to build the first satellite, called ERTS-1 (later renamed Landsat 1), the whole plan still was considered somewhat experimental.

After all, once you launch the satellite, what do you do with all that data? A ground station would have to fill many roles. A 1969 presentation outlined what would be needed: “sending commands to and acquiring data from the satellites; an operations control activity to set priorities on satellite usage and to generate the commands; data handling and processing centers; and the users themselves.”

The presentation offered another insight: “The initial Earth Resources Satellites are expected to use existing NASA ground stations.” The key word here is “initial”: Eventually, all the functions of a ground station might be in one place, but to start out, controlling the satellites and acquiring the data would need to happen at an existing site, which ended up being Goddard Space Flight Center (GSFC). Handling, processing, and researching the data—and getting it into users’ hands—would occur somewhere else. The paper went so far as to suggest that a data center might best be located close to GSFC to increase efficiency.

Choosing Sioux Falls

The data center would bring cachet wherever the USGS built it, with high-tech, space-age technology. The estimated workforce of about 350 would process and store film and develop photography, among other duties.

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EROS program planners faced a dilemma. “We’ve got a problem—everybody would want this!” said Charles Robinove, one of two scientists who pitched the initial idea for EROS to USGS Director William Pecora. “So I said what we need is some criteria, some very specific technical criteria that nobody can argue with, about where this data center should be,” Robinove explained in a 2008 interview. It was those criteria that ultimately resulted in Sioux Falls’ selection: An oval area roughly in the country’s center where data could be received from the lower 48 states.

Pecora later verified that part of the plan was eventually to add an antenna in Sioux Falls. In a 1970 letter to a NASA administrator, he wrote of the data center: “It will be planned to become a reception center for a follow-on operations system, contingent on the success of the ERTS-A and B experiments. Location of the experimental data-use center at Sioux Falls will ease the ultimate transition of the center into an operational mode.”

That is, once the Landsat program proved itself, the EROS Center could anticipate the addition of an antenna and the ability to receive data—and maybe even fly and control the satellite.

Success—and Delays

Landsats 1 and 2 exceeded expectations, contributing exciting scientific discoveries and continuing to operate beyond their planned lifespans. EROS advocates breathed a sigh of relief when Landsat 3 launched on March 5, 1978, proving the value of the program.

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EROS was excelling at its part of ground station duties, too. Not only was there constant improvement in response time to customers, but EROS staffers were working hard to create new customers by conducting training in remote sensing for both international scientists and federal employees from other agencies who could use satellite data. Researchers at EROS studied land change and continuously invented new and better ways to analyze data.

But this was also an era of federal belt-tightening, and bringing ground station capabilities to the center wasn’t yet on the table—despite the fact that canisters of Landsat data had to be shipped continuously to Sioux Falls, mostly via airplane.

An advance in May 1979 ended the era of flying in film: A DOMSAT antenna was installed so GSFC could send information directly to EROS, dramatically reducing turnaround time for customers. Paradoxically, this also eased the pressure to build a ground station at EROS.

Progress Despite Uncertainty

Toward the end of 1979, President Carter signed an order calling for the commercialization of Landsat data, an idea that President Reagan endorsed and accelerated. Even before a company was chosen, daily operations of Landsat were taken over by the National Oceanic and Atmospheric Administration (NOAA), part of the Department of Commerce.

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By September 1985, EOSAT was tapped to be the commercial operator for Landsat and laid immediate plans to build a $10 million ground station at its home base in Norman, Oklahoma, and another outside of Washington, D.C. While EROS was still designated as the archive for Landsat data and for providing customer service, its prospects for achieving ground station status looked increasingly dim.

Against this backdrop of uncertainty, the center received an antenna from NOAA that solidified its science credentials: the Advanced Very High Resolution Radiometer (AVHRR). EROS’ International Program tapped into the greenness-mapping potential of the AVHRR to provide real-life benefits for African countries facing famine, studying where crops were thriving as well as areas where locusts might breed.

Thus, the first satellite data directly received and then studied at EROS came from a NOAA satellite. Meanwhile, the center maintained its archive and researched data from Landsat 4 (launched in 1982) and Landsat 5 (launched in 1984).

Launching a Ground Station

When President George H.W. Bush took office, the trajectory changed for both EROS and the Landsat program. The Bush administration’s emphasis on space boosted NASA’s Mission to Planet Earth in 1990, which resulted in a planned addition to EROS to host the Land Processes Distributed Active Archive Center (LP DAAC).

By 1992, new federal legislation designated EROS as not only the official civilian remote sensing archive but as the future home of the ground station for Landsat 7. This spelled the end for commercialization, which was hastened when Landsat 6 failed to achieve orbit in 1993. The grand opening of the addition in 1996 was followed by the 1997 arrival of the Landsat 7 antenna on June 7.

EROS finally had its own Landsat antenna—but only a month after installation was completed, a devastating storm with baseball-sized hail rendered it unusable. Fortunately, it was reinstalled in plenty of time for the April 15, 1999, launch of Landsat 7, which had faced delays. Three days later, the EROS Center had the satisfaction of processing, for the first time, Landsat data downloaded through its own antenna. And a few months later, installation began for a radome to enclose the antenna and guard against a repeat of the hail damage.

Managing and Monitoring

EROS employees relished the opportunity to operate the antenna as well as monitor each overhead pass of both Landsat 5 and Landsat 7 to ensure that the transfer of data went off without a hitch. In fact, ground station crew members developed the EarthNow! viewer to view the data in real time. They also enjoyed maintaining the radome, which sometimes involved snapping the ropes on the side during snowy weather. It has become a recognizable landmark at EROS.

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But what about Pecora’s original plan, which was for the Sioux Falls center to someday not only receive, archive, and analyze data but also fly the satellites? Well, to start with, in 2000-2001 USGS shared flight operations for Landsats 5 and 7 with NASA—but they were still operated from the Goddard Landsat Mission Operation Center. The same was true for Landsat 8 in 2013. That all changed on August 11, 2022, when NASA officially handed control and command of Landsat 9 to USGS in a ceremony held at EROS. Both Landsat 8 and Landsat 9 are now operated by USGS personnel stationed at Goddard.

However, the dream of flying the satellite from EROS was indeed achieved, if only temporarily: For three days in December 2022, the EROS Center officially hosted the complete operations for Landsat 8 and 9 when a trio of USGS employees from Goddard tested the transfer of satellite operations to the backup Landsat Multi-Satellite Operations Center (bLMOC) for the first time. “The spacecraft didn’t even notice,” noted one of the operators. Plans include biannual testing for the bLMOC.

Modern communications, plus the open data policies of today’s Landsat archive, mean it’s no longer necessary to gather all aspects of a ground station under one roof. Still, it’s nice to know that EROS could pull it off if needed.