When NASA's Nancy Grace Roman Space Telescope launches in October 2026, it won't just be peering into the distant universe to study dark energy and exoplanets. This powerful observatory will also serve as Earth's newest guardian, helping scientists track and understand potentially dangerous asteroids and comets that could threaten our planet.

The Roman Space Telescope will position itself at the Earth-Sun L2 Lagrange point, a gravitationally stable location about 1.5 million kilometres from Earth in the opposite direction of the Sun. From this vantage point, the telescope will use its sensitive near infrared vision to study near Earth objects (NEOs), the asteroids and comets whose orbits bring them close to our planet.

What makes Roman particularly valuable for planetary defence is its ability to measure the physical properties of these space rocks with unprecedented precision. While other telescopes can spot asteroids, Roman will be able to determine their size, shape, composition, and exact orbital paths. This detailed information is crucial for understanding which objects pose real threats and which are harmless.