Tabby's Star — officially known as KIC 8462852 — is acting weird, again. Recent reports indicate it has started to dim in brightness. That's what Tabby's star does — it dims.

Astronomers were ready for the event — they have pointed telescopes from around the world at the star and are currently collecting as many different wavelengths of light as they can.

The thing that makes Tabby's star unusual, is how much it dims — sometimes up to 20%. That's an enormous amount. If our sun dimmed that much, life on Earth would be very different from what it is today.

In fact, Tabby's star is so unusual that none of the regular explanations can describe it. That's what led one astronomer to suggest that aliens might be the reason.

A type of alien megastructure, called a Dyson swarm, could — in theory — explain Tabby's unusual dimming behavior. Most experts agree that aliens are always the last possible answer to any weird observations seen in space.

But until they can disprove this theory, Tabby's star will remain an enigma. These new observations could be exactly what astronomers need to solve the mystery.

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