A moon that orbits a planet or other celestial body outside of our own solar system has yet to be discovered, despite the existence of 6,000 exoplanets. Eksokuu is this elusive moon, and while it is likely much smaller than the planets it orbits, scientists believe that the James Webb Space Telescope may have indirectly discovered it.
This exomoon is thought to orbit a brown dwarf, which is not a planet but a dark “failed star.” Brown dwarfs are bodies larger than Jupiter that have not started a nuclear reaction to become a star, remaining dark instead. The James Webb Space Telescope previously detected surprising infrared methane emission from a dwarf known as W1935, suggesting the presence of a moon or moons interacting with the dwarf.
Further investigation is needed to confirm the existence of this exomoon, but evidence suggests that the aurora borealis on W1935 could be produced by a nearby active moon similar to those found around Jupiter and Saturn in our own solar system. If confirmed, Eksokuu would be an exciting discovery for astronomers studying the outer reaches of our universe.
