One of the weirdest objects ever discovered in our solar system — the alien space rock ‘Oumuamua — is still sparking debates more than two years after its discovery. And, most recently, the conversation has shifted to whether the cosmic visitor could be a fragment ripped from a larger world.

In 2017, the Pan-STARRS asteroid-hunting telescope in Hawaii spotted an object moving at a breathtaking pace of 54 miles (87 kilometers) per second. But, unlike most comets and asteroids before it, ‘Oumuamua would only approach our Sun once before continuing its journey through space. This made it the first known interstellar object to have passed through our solar system.

Scientists named the alien space rock ‘Oumuamua, which roughly translates as “messenger from afar arriving first” in Hawaiian. And though astronomers agree that ‘Oumuamua visited our solar system from another star, that’s about where the agreement ends.

Is it an alien asteroid, an alien comet, or even an alien spaceship?

Now, a pair of astronomers have used complex computer modeling to explain ‘Oumuamua’s combination of strange properties, finding the space rock may be a small shard ripped from a larger parent body.

Their models suggest that when an object — anything from a comet to a super-Earth — passes too close to its star, intense tidal forces can cause heated fragments to slough off. These melted shards then refreeze, locking in their unique shapes.

If these astronomers are right, then we should expect to spot plenty of oddly shaped worlds like ‘Oumuamua in the coming years.

“We anticipate many more interstellar visitors with similar traits to ‘Oumuamua will be discovered by future observation,” says study author Yun Zhang from the National Astronomical Observatories of the Chinese Academy of Sciences.

The new findings were published Monday in the journal Nature Astronomy.