Destroyed Planet or Alien Megastructure: Why Is This Mysterious 'Star' Flickering?

A perplexing celestial body that behaves like no other star has dimmed again, opening up a window of observation for astronomers.

Amateur and professional astronomers alike are scrambling to figure out why the celestial body known as KIC 8462852, or Boyajian's star, is acting so weird.

First observed by the Kepler space telescope in several years ago, KIC 8462852 (also called “Tabby’s star” as a nod to astronomer Tabetha Boyajian, who decoded its signature from Kepler's data in 2015), has dimmed by as much as 22 percent since Friday morning, a dramatic behavior not previously observed in stars.

Scientists now have the opportunity to observe and photograph the star’s dimming behaviour clearly, which astronomers hope will shed light on its mysterious appearance.

An illustration depicts comets passing in front of what Boyajian's star, another theory as to what may cause the flickering.
ILLUSTRATION COURTESY NASA

The star demonstrates perplexing behaviour, appearing to dim and return to its original brightness, or flicker.

Theories abound as to what's going on. Among the most popular are that comets are passing in front of the star, or that a nearby planet has broken apart, blocking our view from Earth with fragments of planetary matter.

Some scientists theorise that the dimming could be due to an “alien megastructure” that's orbiting Boyajian's star and harvesting its energy.

Whatever the object, observations of today’s dimming may help explain why it behaves the way it does.

Header Image: An illustration depicts what Boyajian's star may look like. The star demonstrates inexplicable changes in brightness, and one hypothesis, illustrated here, is that pieces of a broken planet are blocking the star's light. ILLUSTRATION COURTESY NASA/JPL/CALTECH

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