Atmosphere spotted on celestial body in far reaches of solar system |
WASHINGTON (Reuters) — In the far reaches of our solar system, beyond the outermost planet Neptune, resides a host of icy and desolate celestial bodies. Among these objects, only the dwarf planet Pluto was known to possess an atmosphere — until now.
Astronomers have identified another object from this realm, with a diameter of roughly 310 miles (500 kilometers), that has an atmosphere — albeit a thin one — in a discovery that suggests that some of these lonely bodies may be more dynamic than previously known. Researchers are now trying to determine what has caused it to have an atmosphere.
These bodies are called trans-Neptunian objects, and this one is named “(612533) 2002 XV93.” It orbits the sun at roughly the same distance as Pluto.
It is much smaller than the two largest trans-Neptunian objects — Pluto, with a diameter of 1,473 miles (2,370 kilometers), and Eris, with a diameter of 1,445 miles (2,326 kilometers). Pluto and Eris are classified as dwarf planets.
The object’s atmosphere appears to be roughly 5 million to 10 million times thinner than Earth’s robust atmosphere, and about 50 to 100 times thinner than Pluto’s tenuous atmosphere. The researchers said this object’s atmosphere may be dominated by methane, nitrogen, or carbon monoxide.
“The discovery suggests that some small icy bodies in the outer Solar System may not be completely inactive or unchanging, as previously assumed,” said astronomer Ko Arimatsu, head of the Ishigakijima Astronomical Observatory, a lecturer at the National Astronomical Observatory of Japan and lead author of........