EROS, Landsat 9 Ground System Ready for Launch

EROS, Landsat 9 Ground System Ready for Launch

The encapsulated payload stack with Landsat 9 is transported from the Integrated Processing Facility (IPF) to Space Launch Complex (SLC)-3 for hoisting aboard the Atlas V. Photo by United Launch Alliance.

It’s well-known that NASA leads the development and launch of each Landsat satellite, and that USGS builds and manages the ground system and operates each observatory.

What the Landsat 9 mission has made clear, however, is that collaboration begins early and continues throughout the life of each Landsat. That was apparent during a Sept. 15 virtual briefing, when project managers from both agencies extolled the virtues and far-reaching benefits of the partnership. Acting USGS Director David Applegate, for example, noted in remarks on the historical significance of the program that “Landsat has transformed our understanding of Earth, and allows us to better monitor and respond to its many changes.”

Others spoke of the side-by-side relationships that helped bring Landsat 9 into position for a successful launch.

“The USGS has just done a stellar job developing the ground system and operations program for this satellite,” said Del Jenstrom, the L9 project manager for NASA. “Together, our NASA and USGS team have thoroughly tested this with the flight side of the project, and so we are ready to operate this mission.”

Eyes on Earth: Building a Ground System

Collaboration early and often was a through-line for Kari Wulf and Mike O’Brien, contractors for the USGS Earth Resources Observation and Science (EROS) Center, as they discussed their work on the ground system on Episode 59 of the EROS podcast “Eyes on Earth.”

Kari Wulf and Mike O’Brien with the logo for the EROS podcast “Eyes on Earth.” Hear Episode 59 on the Landsat 9 ground system by following this link.

Wulf and O’Brien are among EROS staff who’ve been readying the ground system, with Wulf serving as L9 mission integration lead and ground system manager.

The ground system has three elements, Wulf explained on the show:

The Ground Network Element, which includes in Sioux Falls, SD; Fairbanks, AK; Neustrelitz, Germany; Svalbard, Norway; and Alice Springs, Australia

The Data Processing and Archive System at EROS that processes and archives the data for sharing with the world

The Landsat Multi-Satellite Operations Center (LMOC) in Greenbelt, MD, where operators command and control each satellite.

Including the LMOC team, more than 120 people have worked to prepare the Landsat 9 ground system over the past five years.

As EROS staffers worked to develop the ground station updates, “the development for all the functionality within the LMOC was being built and delivered and installed in the Operations Center at Goddard,” Wulf said. “And simultaneously, the data processing system was being built. They all work together.”

EROS engineers literally built a Landsat 9 ground system in a hallway at a Northrup Grumman facility in Gilbert, AZ as the orbiter’s components were tested. It’s the second use of a “hallway ground system” for Landsat, the first being used for Landsat 8. The first HGS was built out of necessity, O’Brien explained. NASA had used a compatibility test van for previous satellite builds, but that ground system tool was decommissioned before work began on Landsat 8.

The HGS turned out to be a wise replacement strategy. It gave the USGS a way to capture data from the spacecraft and observatory, support data analysis activities, and test ground system functionality with equipment that mirrored the actual equipment used by the international ground stations that collect on-orbit data. NASA engineers and contractors also reaped the benefits. The test data flowing to the HGS from the observatory next door made it possible to pass along early warnings about sensor and spacecraft issues to NASA’s engineers, who could correct the problems more quickly, O’Brien said.

“In Landsat 8, because this was new, we started finding problems with the spacecraft during the build. Problems that weren’t obvious,” he said. “They would have been found, but the previous iteration of the testing was to collect a bunch of data, do the testing, and then ship it off … So it would be weeks before you actually responded. Now, we have a representative ground station in the hall that can detect these errors and problems right away.”

That success with Landsat 8 prompted a more deliberate HGS build for Landsat 9, Wulf said.

“It was a great idea by a group of engineers that said, ‘Hey what if we did this? It may be a great way to capture data and look at the data and test some things out,’” Wulf said. “It really has been an invaluable tool. It has been more broadly used than originally anticipated on Landsat 9.”

Wulf also talked about the Backup Landsat Mission Operations Center (bLMOC) on the show, which will be the first satellite operations center in South Dakota and offer command and control capabilities if trouble occurs at NASA Goddard.

USGS-NASA Partnership Delivers on Landsat Promise

NASA is responsible for the launch and the approximately 100-day commissioning phase of the mission, during which the instruments are checked out and calibrated before daily operations begin. But that phase also involves close collaboration with the USGS.

Mike O’Brien will be in Alaska on launch day with his co-worker Grant Mah, the ground system engineering lead, to oversee the critical first contacts of Landsat 9 with the Fairbanks station and insure the success of command and telemetry activities. Cody Anderson, head of the EROS Cal/Val Center of Excellence (ECCOE) will work alongside his NASA counterparts and other collaborators for Landsat 9’s “underfly” with Landsat 8, during which each satellite will collect data at the same time to allow for comparative calibration.

Each element of testing and preparation on the USGS side is designed to deliver on the Landsat promise: Earth observation data that carries on the program’s 50-year legacy and helps us to understand our planet. As USGS Landsat 9 Project Manager Brian Sauer put it during his portion of the Sept. 15 video briefing, “the ground system performs everything we need to command the satellite, retrieve science data, and turn that data into science products that are distributed to users all over the world.”

It’s been a long road, and EROS New Missions Branch Chief Joe Blahovec is proud of the work EROS has done to ready the USGS for its role in the Landsat mission’s newest observatory.

“We were there through all the ground readiness testing to get us prepared, and the team put in a lot of hours to get us to the point that we can say ‘yes, we’re ready for launch,’” Blahovec said.

Through ground system development and ground readiness testing, through HGS observatory test support and mission readiness test activities and beyond—much of which took place remotely during a global pandemic—the USGS has delivered.

This graphic displays the activities that start as soon as the Landsat 9 satellite is launched. During the 100-day commissioning phase, NASA monitors all aspects of the spacecraft as it travels towards its final orbit height of 705 km (438 mi.) above the Earth. Spacecraft calibration and maneuvers are conducted and verified throughout the commissioning phase to ensure that all systems are operating nominally. At 100 days, ownership of the Landsat 9 mission is transferred to the USGS which begins the operations phase.

Launch to 30 days:

Spacecraft activation, commissioning, and orbital maneuvers are performed.

+30-60 Days:

The first scenes will be acquired from the onboard Operational Land Imager-2 (OLI-2) and Thermal Infrared Sensor-2 (TIRS) instruments allowing NASA and USGS Calibration/Validation experts to verify the quality of data being delivered. During this time, cross calibration exercises between both Landsat 9 and 8 will be performed, a once in a mission’s lifetime simultaneous imaging opportunity. Following this, further spacecraft maneuvers will continue to be performed, ensuring the satellite has established its place in a WRS-2 orbit.

+60-100 Days:

Throughout days 60-100 post launch, verification tests are conducted to ensure routine operations will be successful. A Post-Launch Assessment Review (PLAR) is conducted followed shortly by the Mission Transition and Handover Review (MTHR) which acts as a final review. The MTHR is an important event, after which responsibility and ownership of the Landsat 9 Mission is transferred from NASA to the USGS.

+100 Days (early 2022):

After 100 days, the USGS conducts nominal science operations, maintains routine acquisitions, as well as performs ongoing Calibration/Validation of the data. Landsat 9 Level-1 data and Level 2 science products will then become available at no cost to all users through the USGS data portals.

Please visit the Landsat Mission and Landsat 9 webpages for more information.

(Public domain.)


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