Atmosphere found on a small icy body beyond Neptune ⚡ экспресс
For a long time it was believed that only Pluto in the outer Solar System has an atmosphere. But astronomers have discovered a thin gaseous shell around object 2002 XV93—an icy world three times smaller than Pluto. It's like finding that a small pebble breathes, when we used to think only big ones could. And how many more such 'breathing' dwarf planets are hiding in the dark?
Beyond Neptune, in the icy belt, astronomers watched as object (612533) 2002 XV93 momentarily occulted a distant star. Using метод прохождений (when a planet dims the star's light for a second, like a fly in front of a lamp), Уильям Боруки and Дэвид Шарбонно determined: the light not only dimmed but also shifted in hue — like the air above a campfire. This revealed a thin gaseous veil around a body with a diameter of 250 km. The veil consists of nitrogen with traces of methane and rests on an icy surface. The pressure there is millions of times lower than Earth's — if our atmosphere were like that, a breath would be empty. The veil could be sustained either by icy fountains—cryovolcanoes erupting from the interior—or by an impact from another fragment that knocked out gases. This world is the only one among its neighbors (even Eris and Makemake are silent) that has managed to keep such a ghostly cloak.
🎯 The shadow of this object on Earth was as wide as a small town; it was caught thanks to dozens of volunteer telescopes.