Planetary Defense Faces a New Reality As Interstellar Objects Like 3I/ATLAS Become More Common

Interstellar objects compress that timeline.

Unlike asteroids that orbit the Sun repeatedly and can be cataloged years or decades in advance, interstellar objects arrive once, on hyperbolic trajectories, often at high speeds. By the time they are detected, they may already be deep inside the solar system. That reality makes early discovery the most critical element of planetary defense in the coming decade.

This is where the Vera C. Rubin Observatory enters the picture.

Already operational, the Rubin Observatory in Chile is designed to repeatedly scan the entire visible sky every few nights, creating the most comprehensive time-domain survey of the universe ever attempted. Its Legacy Survey of Space and Time is expected to detect millions of solar system objects, including near-Earth asteroids, comets, and—critically—interstellar interlopers like 3I/ATLAS.

Scientists widely expect that once Rubin comes fully online, discoveries of interstellar objects will shift from rare events to routine occurrences.