On June 14 and 16, technicians installed solar panels onto NASA’s Nancy Grace Roman Space Telescope, one of the final steps in assembling the observatory. Collectively called the Solar Array Sun Shield, these panels will power and shade the observatory, enabling all the mission’s observations and helping keep the instruments cool.

“At this point, the observatory is about 90% complete,” said Jack Marshall, the Solar Array Sun Shield lead at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We just need to join two large assemblies, and then we’ll run the whole Roman observatory through a series of tests. We’re currently on track for launch several months earlier than the promised date of no later than May 2027.” The team is working toward launch as early as fall 2026.
The Solar Array Sun Shield is made up of six panels, each covered in solar cells. The two central panels will remain fixed to the outer barrel assembly (the observatory’s outer shell) while the other four will deploy once Roman is in space, swinging up to align with the center panels.
The panels will spend the entirety of the mission facing the Sun to provide a steady supply of power to the observatory’s electronics. This orientation will also shade much of the observatory and help keep the instruments cool, which is critical for an infrared observatory. Since infrared light is detectable as heat, excess warmth from the spacecraft’s own components would saturate the detectors and effectively blind the telescope.

“Now that the panels have been installed, the outer portion of the Roman observatory is complete,” said Goddard’s Aaron Vigil, a mechanical engineer working on the array. Next, technicians will test deploy the solar panels and the observatory’s “visor” (the deployable aperture cover). The team is also testing the core portion of the observatory, assessing the electronics and conducting a thermal vacuum test to ensure the system operates as planned in the harsh space environment.
This will keep the project on track to connect Roman’s inner and outer segments in November, resulting in a whole observatory by the end of the year that can then undergo pre-launch tests.
To virtually tour an interactive version of the telescope, visit: https://roman.gsfc.nasa.gov/interactive/
Download high-resolution video and images from NASA’s Scientific Visualization Studio
The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems Inc. in Boulder, Colorado; L3Harris Technologies in Rochester, New York; and Teledyne Scientific & Imaging in Thousand Oaks, California.
By Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.