Engineers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland have completed testing a high-gain antenna for the Nancy Grace Rome Space Telescope. When it enters service in May 2027, this NASA observatory will help unravel the mysteries of dark energy and dark matter, search and image exoplanets, and explore many topics in infrared astrophysics. The antenna, pictured below in the test chamber, will provide the primary link between the Roman spacecraft and Earth. It will transmit the largest amount of data of any NASA astrophysics mission.

The antenna reflector is made of a carbon composite material that weighs very little but is still resistant to the spacecraft’s significant temperature fluctuations. The dish is 5.6 feet (1.7 meters) in diameter, about as tall as a refrigerator, but weighs just 24 pounds (10.9 kilograms). Its large size will help Roman send radio signals to Earth millions of kilometers from space. On a single frequency, a dual-band antenna will receive commands and send back information about the spacecraft’s status and position. It will use a different frequency to stream data at speeds of up to 500 megabits per second to ground stations in New Mexico, Australia and Japan. These locations are distributed so that the Roman team can always communicate with the spacecraft.

The manufacture of this antenna was a coordinated effort between the government and the commercial sector. NASA was responsible for the development of radio frequencies and the manufacture of the supply units. Commercial partner, Applied Aerospace Structures Corporation (AASC) of Stockton, California, is contracted for the final mechanical flight design and fabrication of the composite reflector and support. The finished antenna was delivered to NASA in December.

Engineers at AASC and Goddard have extensively tested it to confirm that it will perform as expected in the extreme conditions of space, where it will operate in the temperature range of minus 26 to 284 degrees Fahrenheit (minus 32 to 140 degrees Celsius). The team also tested the antenna for vibration to ensure the spacecraft would survive launch. Engineers measured the performance of the antenna in the RF anechoic test chamber pictured above.

Every surface in the test chamber is covered with pieces of pyramidal foam that minimizes obstructive reflections during testing. Next, the team will attach the antenna to the jib assembly and then electrically connect it to the Rome radio frequency communication system.