Asteroid 152637 (1997 NC1) to make closest Earth approach in 400 years on 27 June 2026

On 27 June 2026 the near‑Earth asteroid 152637 (1997 NC1) will pass within about 2.56 million km of Earth, the nearest distance recorded for this object in four centuries and not expected to repeat until after 2133. The roughly 900‑metre to 1.5‑kilometre‑wide body belongs to the Aten class and its trajectory poses no impact risk for the foreseeable future.

Astronomers worldwide will monitor the fly‑by with optical telescopes and high‑power radar, including NASA’s Goldstone system, to refine its shape, size, rotation and orbital parameters. Data gathered will improve long‑term planetary‑defence models and orbital predictions for similar objects. The asteroid will reach a visual magnitude of about 10, making it observable with modest amateur telescopes.

The event offers a rare opportunity for both professional and amateur observers to collaborate on precise positional measurements and to test the capabilities of modern space‑hazard surveillance networks.