When an astronomer makes a light suggestion that aliens might be responsible for something weird happening in space, people pay attention. And that’s what kicked off the ballyhoo about KIC 8462852 (affectionately known as Tabbys Star) back in October 2015. When we observe a star to be brightening and dimming on a regular cycle, it’s because it has a planet or other object in its orbit. But Tabby’s Star’s dimming patterns were so irregular that a clear explanation couldn’t be found.

What if the reason was artificial in origin? One astronomer provided a hail mary reason: megastructures built by super-advanced aliens.

In the ensuing months, researchers have poured a lot of time and energy into trying to figure out exactly what was happening in Tabby’s neighborhood and hopefully pinpoint or more natural explanation. While there are some theories — orbital debris, comets, among others — but nothing has been confirmed, and the mystery is only getting weirder.

And now, a new complication has arisen. An international team of researchers have just observed another series of aberrant dimming events surrounding a new star, RIK-210, about 472 light-years from Earth. And as with Tabby’s Star, the team is stumped about what’s going on with RIK-210, according to a new paper uploaded to the arXiv repository.

The young star is dimming by up to 15 percent every 5.67 days, and it’s correlating with the star’s rotation. The team has already thrown out possible explanations pertaining to companion brown dwarf stars. There are no planets in orbit because the star, just a wee 5 to 10 million years old, doesn’t even yet have the kind of ring of dust and gas that creates a nursery for young planets.

The team thinks the most likely cause of the strange dimming is a cloud that’s strapped in the star’s magnetosphere. This kind of object would orbit the star at the same speed of the star’s spin.

Naturally, this is just speculation, and the researchers will need to conduct a slew of follow-up observations to determine this. And for that reason, we still can’t definitively throw out other possible theories, like — you guessed it — alien megastructures.

Needless to say, the suspense is killing us.

Photos via NASA/JPL-Caltech