Roman telescope asteroid detection is being pitched as an extra job for NASA’s Nancy Grace Roman Space Telescope, not a conversion of the observatory into a planetary-defense mission. A multi-institutional group plans to present the idea at a September conference, according to MIT Technology Review: use Roman’s broad infrared surveys to find and characterize some moving objects that pass through its fields of view.
That distinction is doing real work. The proposal is not a NASA announcement that Roman has been assigned asteroid operations, and the supplied reporting does not establish that NASA has adopted the plan. Roman was designed for astrophysics. NASA’s earlier material on the telescope’s WFIRST predecessor says investigating dark energy, the still-unexplained driver of the universe’s accelerating expansion, was among its central scientific purposes.
The attraction is hardware already headed to space. MIT Technology Review reports that Roman carries a 300-megapixel, wide-angle infrared camera with a view about 100 times Hubble’s. Its normal surveys will look beyond the solar system, but nearby asteroids can cross those images too.
How could Roman telescope asteroid detection work?
Researchers estimate Roman could spot asteroids about 60 feet long, MIT Technology Review reports. Infrared observations can also help researchers assess an object’s size and composition, rather than relying only on reflected visible light.
There is an awkward implementation detail: Roman’s processing is built to identify streaks in images, including those from cosmic rays, instrument glitches and asteroids, and discard them as unwanted artifacts. Johns Hopkins Applied Physics Laboratory planetary scientist Andy Rivkin told MIT Technology Review that asteroid work would require astronomers to inspect those streaks, or alter the handling so relevant data are retained. Until that happens and the capability is demonstrated, the estimate remains a proposal rather than an operational result.
Roman’s proposed role is breadth, not precision study of every candidate. The telescope could gather infrared measurements for many questionable objects across a large patch of sky. The most consequential targets could then go to narrower or more time-intensive instruments, including the James Webb Space Telescope, for closer observations, according to MIT Technology Review.
How is Roman different from NEO Surveyor?
NASA’s planned Near-Earth Object Surveyor is the dedicated system in this picture. Science reported that the infrared observatory was being assembled for a planned September 2027 launch, with the goal of helping find nearly all near-Earth asteroids at least 140 meters long. It is intended to observe closer to the Sun than ground telescopes can manage, addressing objects hidden in solar glare as well as dark or unusually orbiting asteroids.
Roman would not replace that mission. It could add survey capacity while pursuing its own cosmology program, if NASA and its scientists make the software and observing choices needed to use the data that way.
The gap is substantial. MIT Technology Review says NASA’s Planetary Defense Coordination Office is chiefly concerned with near-Earth asteroids at least 460 feet long, a group estimated at roughly 25,000 objects, with just over half still undiscovered. Finding objects is only the first step; orbit calculations and follow-up observations determine whether an initially uncertain candidate poses any risk.
This story draws on original reporting from MIT Technology Review.
