A group of researchers claims to have found what may be the first exoplanet ever discovered in a different galaxy.

Although our galaxy may have billions of exoplanets, it is much more difficult to discover new planets even in the nearby galaxies. Now, according to a story in New Scientist, a team of Harvard-Smithsonian scientists may have finally overcome that limit thanks to evidence that a planet-sized object is orbiting a binary system in the Whirlpool galaxy.

Over the years, a few scientists found signs of exoplanets in other galaxies, but none have ever been confirmed. The same is true for this potential exoplanet, according to preprint research shared online last week. But still, scientists are cautiously optimistic.

“It’s exciting, but not unexpected,” Angelle Tanner, a Mississippi State University astronomer who didn’t work on the study, told New Scientist. “There’s absolutely no reason to think there wouldn’t be planets in other galaxies.”

Unfortunately, any confirmation could be entire decades away, New Scientist reports. The team found evidence that an object the size of Saturn — potentially a gas giant itself — passed in front of one of the stars in its binary system. But because it’s also orbiting at about the same distance as Saturn does our Sun, it might be decades before it does so again, at which point scientists could confirm the discovery.

“It could be something that just passed in front of this system, never returning again,” Tanner said.

READ MORE: Astronomers may have found the first planet in another galaxy [New Scientist]