NASA has now confirmed all ground stations supporting the agency's Nancy Grace Roman Space Telescope are ready to receive the mission's high volume of data once science operations begin by early 2027.

Observing the far reaches of the cosmos wouldn't be possible without a network of ground stations strategically located around the world serving as a tether between Earth and space. Ground stations from NASA's Near Space Network in New Mexico, ESA (European Space Agency) in Australia, and JAXA (Japan Aerospace Exploration Agency) in Japan will receive the science data at extremely high data rates, up to 500 megabits per second.

Recent testing ensured that these stations will be able to receive approximately 1.4 terabytes of data that Roman will downlink each day, the highest rate of any NASA astrophysics mission so far, from Roman's location a million miles away in space.

To confirm this capacity, scientists began drawing down "housekeeping" information.

"This is real, operational data starting with details about how the instruments are doing, things like temperature, power draw, and preliminary image data," said Bob Kalogerakos, a radio frequency engineer at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

The Roman team started with JAXA's Misasa Deep Space Station in Saku City on Sept. 7. Engineers tested out the station's antenna and confirmed it can receive data at rates up to 500 megabits per second throughout most of the year. The rate will vary with Roman's distance from and elevation relative to Earth as it orbits the Lagrange point 2, or L2.

"This was our first time downlinking data at Roman's maximum rate," said Matthew Wasiak, an advanced systems engineer at NASA Goddard. "There was also a typhoon in Japan during the test and conditions were not perfect, which makes this a particularly rigorous test."

Adverse weather can create a major obstacle for drawing down space telescope data because raindrops are not much smaller than the radio wavelengths Roman is using to send its data. That means they can scatter or weaken the signals.

"Because of this, we have a diversity of ground stations, from the subtropical island of JAXA's ground station in Japan to the arid Western Australian desert to summer monsoon-prone New Mexico." Kalogerakos said. "When weather and rain do interfere with our signal, our automated ground systems will determine what data didn't downlink properly and ask the spacecraft to re-transmit from its onboard solid-state recorder in a few hours."

Engineers have successfully tested this Near Space Network antenna, located in White Sands, New Mexico. This ground station will help bring data from NASA's Nancy Grace Roman Space Telescope down to scientists on Earth.

NASA

After the Misasa Deep Space Station passed the team's tests, their focus shifted to the Near Space Network ground station and its backup in White Sands, New Mexico, from Sept. 8 to 11. Both antennas successfully downlinked data at the rates the team tested.

Finally, the team tested the ESA station, located near New Norcia in Western Australia, on Sept. 17. Again, engineers cycled through different rates, and the ground system successfully downlinked even the highest.

"These ground stations are Roman's primary conduit to get our data down to Earth, and the team is thrilled with their exceptional performance," said Jeremy Perkins, Roman's observatory integration and test scientist at NASA Goddard. "It's great news for a mission that will send back data at an incredible pace."

Bringing Roman's data to the ground is an international effort. NASA's Near Space Network ground station in New Mexico receives Roman's science data in partnership with antennas from ESA in Australia and JAXA in Japan. Managed by NASA's Jet Propulsion Laboratory in Southern California, the agency's Deep Space Network stations in California, Spain, and Australia provide critical tracking data, observatory telemetry, and command.