NASA’s new dark energy space telescope can also detect killer asteroids

At the end of August, NASA is set to launch the Nancy Grace Roman Space Telescope from Kennedy Space Center in Florida. Its quest is to help us better understand how the universe works, from the glue-like dark matter that keeps galaxies together to the elusive dark energy that drives the expansion of the cosmos. But Roman could also serve another purpose: defending Earth from killer asteroids. In September, a multi-institutional team of planetary scientists and astronomers will outline how the space telescope is uniquely placed to scan asteroids, and provide information about their trajectories, sizes and compositions.

Roman, named after NASA’s first chief astronomer, is equipped with a super-wide-angle, 300-megapixel infrared camera, allowing it to see a large patch of space at any one time—roughly 100 times larger than the Hubble Space Telescope. That will allow it to discover thousands of new planets, tens of thousands of exploding stars, and survey over one billion galaxies in remarkable detail.

While doing so, it’ll be looking ‘through’ our solar system, and this is what makes it uniquely well-placed to spot asteroids.

A planetary defense pivot

Roman was not built for this purpose, but last summer, it was ( once again ) threatened with significant funding cuts by the Trump administration . “My colleague Rick Cosentino [a planetary scientist at NASA] said to me in July 2025 that we need to show what Roman can do for planetary defense as a way to further increase the visibility of the mission with lawmakers and taxpayers,” says Bryan Holler , a researcher at the Space Telescope Science Institute in Baltimore, Maryland.

Holler and his colleagues’ proposal , which will be presented at the Europlanet Science Congress at The Hague in The Netherlands, reveals that Roman’s epic field-of-view and infrared vision allows it to spot small asteroids up to 60 feet long. This is comparable to the asteroid that exploded above the Russian city of Chelyabinsk in 2013, unleashing the force of 500,000 tons of TNT and sending 1,500 people to the hospital.

Roman’s software will need some tweaking to spy space rocks. The telescope, as designed, will see through – and beyond – the solar system in order to gather the clearest possible pictures of the rest of the universe. “Streaks, whether caused by cosmic rays or glitches or asteroids, are caught by the software and discarded,” says Andy Rivkin , a planetary scientist and planetary defense researcher at Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. But astronomers could go in, study those streaks and pick out those they identify as asteroids.

Even with those potential adjustments, Roman won’t be an asteroid-finding wunderkind on its own. Its strength lies in complementing the James Webb Space Telescope (JWST), another observatory that’s built to peer at galaxies and stars at the far reaches of the universe. It can also intensely focus on a single asteroid, when needed—as it did last year, playing a key role in tracking 2024 YR4, which was briefly the most dangerous asteroid ever discovered. “But Roman’s field of view is much bigger,” says Rivkin.