Nasa's $4.3bn Nancy Grace Roman space telescope, which survived two rounds of proposed White House budget cuts, is set to lift off from Florida early on Sunday. The launch is scheduled for 7.26am ET from the Kennedy Space Center, barring late technical issues or interference from Florida's summer weather.
The telescope will embark on a million-mile journey into deep space, joining the Hubble and James Webb space telescopes in Nasa's history of space exploration. Named for the agency's first chief of astronomy, who died in 2018, Roman is many times more powerful than Hubble and will work to enhance the output of its stablemates, both of which continue to operate.
Searching for exoplanets and planet formation clues
Roman's primary mission is to search for exoplanets and clues about planetary formation. According to Nasa, its 300-megapixel infrared camera will give Roman the same sharpness and resolution as Hubble, but with a field of view at least 100 times larger. Each image will capture a patch of sky about 1.5 times bigger than the apparent size of a full moon.
The telescope also contains a specialized instrument called a coronagraph that blocks glare from stars, making it easier to photograph planets around them in detail. Nasa said it expected the images would reveal "giant worlds that are older, colder, and in closer orbits than the hot, young super-Jupiters direct imaging has mainly revealed so far".
Destination and mission details
Roman's destination is Lagrange point 2, a "parking spot" in space about one million miles from Earth, where it will operate in the same complex sun-Earth orbit as Webb, though the two telescopes will remain far apart. It is not entirely a successor to Hubble and Webb, launched in 1990 and 2021 respectively, but was designed to support and advance their missions while making discoveries of its own.
Nasa said Roman's large panoramas would "uncover interesting targets that Hubble could follow up on using infrared, visible, and ultraviolet light to offer a more comprehensive view", while Webb "can then use its larger mirror and more powerful vision to deliver even more detailed, ultra-sharp observations". Roman can view regions around objects Hubble or Webb observe "to offer context".
Political battles and final flight
Julie McEnery, Nasa's senior project scientist for the Roman mission, said the need for it was conceived at the end of the last century, although Nasa only began the development stage in 2016, and 2020 before it finally approved the entire project and commenced construction. "One of the motivations for Roman was the discovery that our universe is not just expanding, but that expansion is accelerating," she said in an interview on Thursday with Sophia Roberts, an astrophysics video producer at Nasa's Goddard space flight center in Maryland.
If the US president had his way, Roman would never have made it to the launchpad. A 2025 White House proposal for what analysts said would be "extinction level cuts" to Nasa's science budget, including the axing of the Roman project, was roundly rejected in January by Congress, which restored the agency's 2026 funding level to $24.4bn. The Trump administration is trying again for the 2027 fiscal year, seeking a 23% reduction in Nasa's overall budget to $18.8bn, and a 46% chop for science projects that the Planetary Society said would lead to the termination of more than 50 missions.
Sunday's scheduled launch marks the final flight of SpaceX's Falcon Heavy rocket, which Elon Musk's company is phasing out along with its smaller Falcon 9 rockets to concentrate on Starship, its versatile new workhorse planned to eventually carry humans to Mars. Roman's imagery, which Nasa expects will first come in early 2027 after months of calibration and tests in the telescope's final orbit, will be made immediately public. "From objects in our outer solar system and exploding stars, to growing black holes and galaxies by the billions, very little will be beyond Roman's reach," Nasa said in an online explanation of the telescope's initial five-year mission, which could be extended to 10. "Roman will pair a large field of view with crisp infrared vision to scan vast, deep swaths of sky. This flagship mission is designed to help astronomers explore dark matter, dark energy, and planets outside our solar system."
