The Roman Space Telescope passes a major milestone as construction wraps and the team shifts into final checks before its 2027 debut. At the end of November, NASA’s next flagship observatory—the Nancy Grace Roman Space Telescope—completed assembly. The project teams at NASA’s Goddard Space Flight Center in Maryland joined the telescope’s inner and outer structures, finalizing a multi-billion-dollar instrument on track to launch aboard SpaceX’s Falcon Heavy in May 2027.
With construction finished, Roman moves into final testing. After this testing phase, the observatory will be packed and transported to the Kennedy Space Center, where it will launch from Launch Complex 39A. NASA anticipates shipping the telescope during the summer season.
“Finishing the Roman observatory marks a defining moment for the agency. Breakthrough science hinges on disciplined engineering, and this team has delivered—step by step, test after test—an observatory that will broaden our understanding of the universe. As Roman enters its final testing phase following integration, we are focused on precision and readiness to ensure a successful launch for the global scientific community,” stated Amit Kshatriya, NASA’s Associate Administrator.
Roman’s origins trace back to 2010, when the National Research Council’s Decadal Survey named the Wide-Field Infrared Survey Telescope (WFIRST) NASA’s top priority for the coming decade in astronomy. The WFIRST Design Reference Mission 1 underwent study from 2011 to 2012 to explore potential designs. In 2012, NASA considered a second-hand telescope built by Harris Corporation for the National Reconnaissance Office (NRO) for a wide-field survey mission akin to WFIRST. After a thorough review, the NRO telescope was selected, with plans to add a coronagraph instrument enabling direct exoplanet imaging.
In February 2016, officials chose a halo orbit at the Sun-Earth L2 point for the mission, after evaluating a geosynchronous alternative. By late 2018, NASA awarded the construction and operations contract to Goddard Space Flight Center in Greenbelt, Maryland, which also oversees the Hubble and James Webb Space Telescopes. In March 2020, NASA approved WFIRST for implementation, and in May NASA Administrator Jim Bridenstine announced that WFIRST would be named the Nancy Grace Roman Space Telescope in honor of NASA’s first Chief of Astronomy and the agency’s first female executive.
The mission’s primary mirror was shown before integration as part of the assembly process. The project cleared its critical design review in 2021, updating timetables to account for disruptions from the COVID-19 pandemic. A 2027 launch date was set, with flight hardware fabrication expected to finish by 2024, after which construction moved forward at Goddard.
In July 2022, NASA announced SpaceX would handle Roman’s launch on a Falcon Heavy from LC-39A in Florida, with a projected launch cost around $255 million. Construction of the satellite bus—the nerve center housing most instruments and electronics—finished in September 2024. By December, the telescope’s instruments and the mirror assembly had been integrated onto the satellite bus, and Roman underwent a spin test in October 2024.
On November 25, 2025, NASA confirmed that Goddard teams had completed the entire telescope, clearing the path for final testing and launch preparations.
Roman’s science payload comprises two instruments designed for a distant-L2 mission. The Wide Field Instrument (WFI) and the Coronagraph Instrument (CGI) will be carried to L2. The WFI is a 288-megapixel camera capable of visible and near-infrared imaging, featuring one wideband filter and six narrowband filters. With the WFI, Roman will survey large portions of the sky, delivering an image roughly 200 times larger than Hubble’s Wide Field Camera 3 would in a single exposure.
The mission envisions three primary surveys with the WFI, which will account for about 75% of the telescope’s five-year primary science program. These are the High-Latitude Wide-Area Survey, the High-Latitude Time-Domain Survey, and the Galactic Bulge Time-Domain Survey. The remaining 25% of the WFI’s five-year plan will be made available to the wider astronomy community for broader use.
“The sheer volume of data Roman will produce is staggering and will enable a host of transformative investigations,” explained Dominic Benford, Roman program scientist.
The CGI serves as a technology demonstrator for future exoplanet imaging missions. By suppressing the glare of a host star, the CGI can reveal orbiting exoplanets. It will operate in the 575–825 nm range using a dual deformable mirror-based starlight suppression approach. If this approach succeeds, similar technology could underpin future missions like the Habitable Worlds Observatory.
Four directly imaged exoplanets around the star HR 8799 were captured with a coronagraph on the Keck Observatory, illustrating the kind of capability Roman aims to advance. Feng Zhao, CGI manager, noted, “The question of whether we are alone in the universe is enormous, and it requires equally ambitious tools to explore it. The Roman Coronagraph brings us closer to that goal, and it’s remarkable to test this hardware in space aboard such a powerful observatory.”
After arriving at L2, the CGI team will conduct a curated set of observations during the instrument’s early phase to verify performance. Those checks will occupy about three months of Roman’s first eighteen months of operations. Once this commissioning window closes, the CGI will be released for use by the broader astronomy community.
“The completion of Roman’s construction puts us at the threshold of extraordinary scientific discovery. In the first five years, we expect to catalog more than 100,000 distant worlds, study hundreds of millions of stars, and survey billions of galaxies. This rush of new data will accelerate our understanding of the cosmos,” said Julie McEnry, Roman’s senior project scientist.
Lead image: Members of the Roman team viewing the fully assembled telescope at the Goddard Space Flight Center. Credit: NASA/Jolearra Tshitey
