Japanese Astronomers Discover Unexpected Atmosphere on Distant Kuiper Belt Object
Japanese astronomers have discovered a thin atmosphere surrounding a trans-Neptunian object, designated (612533) 2002 XV93, located in the Kuiper Belt. This object, known as a 'plutino,' is in a 2:3 orbital resonance with Neptune and measures approximately 311 miles across, making it significantly smaller than Pluto. The discovery was made during a rare stellar alignment, where the object passed in front of a distant star, causing a subtle dimming of starlight. This dimming suggested the presence of an atmosphere, which is unexpected given the object's small size and cold environment. The findings, published in Nature Astronomy, challenge existing assumptions about which celestial bodies can sustain atmospheres. The atmosphere is estimated to be extremely thin, about 5 million to 10 million times thinner than Earth's, and is not expected to be permanent. 
