James Mang

At Alpha Centauri A, the nearest Sun-like star, Webb briefly picked up a dot called S1 — a planet candidate the size of Jupiter but with a temperature around –20°C. The object hid behind the star — its orbit lasts just 2–3 years, and there’s remarkably little dust around.

Astronomers analyzed data on the orphan planet WISE 0855 — a dim, cold ball not far away. For 11 hours, Webb watched its light, trying to spot the shadow of a moon. No direct discovery happened, but the method proved its worth. If many rogue planets have Titan-sized moons, we will soon find them.