A first since Pluto: Did a comet explosion create atmosphere on this object beyond Neptune?

Scientists have found an atmosphere around an object beyond the orbit of Neptune which measures only 500 kilometres across. This is the first time that a trans-Neptunian Object (TNO) has exhibited an atmosphere since it was observed on Pluto. Decades of scientific theories suggest that such a small icy body should not be able to exhibit this phenomenon, which is why the findings challenge the idea of how distant bodies in the Solar System evolve. Known as (612533) 2002 XV93, this body lies in the Kuiper Belt and is smaller than Pluto ( 2,377km across). Something as small as this object in the Kuiper does not have sufficient gravity to hold onto an atmosphere for long periods.

The discovery was made by a team of astronomers led by Ko Arimatsu at the National Astronomical Observatory of Japan. The object in the Kuiper was observed in January 2024 when it passed in front of a distant star. This is known as stellar occultation, and when this happens, the light of the star at the back changes when the foreground object moves across it. When it disappears sharply, it means the body has no atmosphere. However, if it dims gradually, it shows that there is gas around the object. The data proved that the latter was true. Also Read: Sun may spare Earth and Mars, as study reverses course on death of our planet

An atmosphere for only 1,000 years

But this atmosphere is not expected to last long, as evidence suggests it should stay for only about 1,000 years. The James Webb Space Telescope hasn't detected any frozen surface gases either, which could sustain the atmosphere by slowly evaporating. The origin of the atmosphere remains unclear. Scientists have proposed two methods that it could have formed. First, certain material from inside the object could have only recently reached the surface. Second, a comet explosion released material into space, some of which settled on (612533) 2002 XV93, creating an atmosphere. Also Read: Lease for life on Earth extended as study finds end of times are at least 1.84 billion years away

This is the first time that a TNO has displayed signs of an atmosphere. "A thin atmosphere has been observed around Pluto, but studies of other trans-Neptunian objects (TNOs) have yielded negative results."