Lauri Jetsu, an astrophysicist at the University of Helsinki, is following a tradition that may stretch back thousands of years.

For more than a decade, he’s studied the bright star Algol, one of the most unusual stars in the sky, with its brightness visibly changing every few days. His research suggests those fluctuations have been noted since at least ancient Egyptian times, and he believes observations made more than 3,000 years ago can contribute to the modern scientific understanding of why Algol behaves as it does.

Jetsu’s latest study, published last month in the Astrophysical Journal, suggests the so-called “Demon Star” could be orbited by up to five more stars, most of them too dim to see.

“It was a surprise to me,” he said. “The probability of finding just two more stars is very low. No one has found this many.”

Algol takes its name from the Arabic phrase “Raʾs al-Ghūl,” meaning “the Demon’s Head” — a name shared by a villain in “Batman.” It’s long been considered an “unlucky star,” possibly because of its changes in brightness.

More: After many centuries, research suggests new facets to the blinking ‘Demon Star’