Tiny Kuiper Object Has an Atmosphere

A Nature Astronomy study led by Ko Arimatsu reports a tentative detection of a very thin, global atmosphere around the plutino (612533) 2002 XV93 (~300 miles / ~500 km across), observed via stellar occultation from more than 3.4 billion miles away. The atmosphere is estimated to be 5–10 million times thinner than Earth's (and 50–100× thinner than Pluto's) and could be composed of methane, nitrogen, or carbon monoxide produced by episodic outgassing or impacts; Webb Telescope observations are proposed to confirm composition. — If confirmed, this expands the catalogue of active, atmosphere‑bearing bodies in the outer solar system and affects models of volatile retention, small‑body geology, and priorities for telescope and mission follow‑up.