The ground-station network dedicated to the Nancy Grace Roman Space Telescope has successfully received real operational data and preliminary data from its scientific instruments, in an early test of the observatory’s ability to transmit the vast quantities of information it will collect during its mission. The US National Aeronautics and Space Administration (NASA) launched the telescope on 30 August 2026 aboard a Falcon Heavy rocket.
Roman network receives first operational data
The data received on Earth included information about the telescope’s instrument status, temperatures and power consumption, along with preliminary data from its scientific instruments. The successful connection is a key part of operating the observatory, which is designed to transmit about 1.4 terabytes of data per day at a target speed of up to 500 megabits per second.
The mission does not rely on a single ground station. Instead, it uses a geographically distributed network to limit the impact of weather conditions and maintain communications continuity.
Communications tests conducted through three stations
During September, NASA tested stations in Japan, New Mexico and Australia. Japan’s Misasa station successfully received the data, followed by a test of the Near Space Network station at White Sands in New Mexico, and then a European Space Agency station near New Norcia in Australia. The network was designed to cope with varying weather conditions that may affect radio signals, including rain.
The ground systems can identify parts of the data that did not arrive and then send a request to the spacecraft to retransmit them from the data recorder on board, reducing the likelihood of information being lost during transmission. Bob Callogerakos, a radio-frequency engineer at NASA’s Goddard Centre, said the stations had received real data, including information about the instruments’ status and temperatures and the amount of power they consumed.
Engineers also tested data transmission at the maximum target rate for the first time, although conditions during one test were not ideal because of a typhoon that struck Japan. The Roman Telescope is meanwhile continuing its journey to its final position near the second Lagrange point, about 1.5 million kilometres from Earth.
Telescope nears start of scientific mission
The observatory is scheduled to begin its scientific mission after completing its commissioning and calibration phase, which will take about 3 months and include adjusting and focusing its instruments and verifying their performance. On 15 September, NASA announced that it had switched on the Wide Field Instrument, an infrared camera with a resolution of 300 megapixels.
The Coronagraph Instrument has also begun initial tests as part of the continuing preparations before the telescope moves to full scientific observation operations. Roman is expected to send its first scientific images in early 2027, after completing adjustment, focusing and calibration operations.
Wide-field observations to support the study of the structure of the universe
Its wide field of view will allow it to survey large areas of the sky over short periods to study dark energy, dark matter and planets outside the Solar System, as well as galaxy evolution and the structure of the universe on a large scale. The broad scope of the observations means the mission will continuously produce large quantities of data that need to be transmitted, stored and processed.
Jeremy Perkins, an observatory integration and test scientist at the Goddard Centre, said the ground stations were the main channel for delivering Roman’s data to Earth and that their successful performance was a good sign for a mission that will transmit information at a high rate.
The tests therefore extended from the telescope’s instruments in space to the ground reception systems that will make the data available to scientists, rather than being limited to verifying the communications link alone.
This process tests the full operational chain, including recording and transmitting information, identifying missing sections and requesting their retransmission before the data are stored and scientifically processed.
