An exomoon signal found in archival data hints at the possibility of more discoveries to come.
Astronomers have reported a second, super-sized moon orbiting a found orbiting a similar Jupiter-sized planet, Kepler 1625b.
Both supermoon candidates are likely made of gas that has piled up under the gravitational pull caused by their enormous size, said Kipping. If one astronomer’s hypothesis is correct, the moons may have even started life as planets, only to be pulled into the orbit of an even bigger planet like Kepler 1625b or 1708b.
Both moons are located far from their host star, where there’s less gravity to tug at planets and strip off their moons. In fact, the researchers sought out cold, giant gas planets on wide orbits in their search for exomoons precisely because the analog in our own solar system, Jupiter and Astronomers Discover Evidence of Super-Sized Moon Orbiting a Jupiter-Sized Planet