Kepler, launched to observe the stellar dimmings caused when an exoplanet passes in front of its star, revealed that the dimming of Tabby’s star was much more erratic than a typical planetary transit.
It was also more extreme, with its brightness sometimes dropping by as much as 20%.
In 2015 a team of astronomers announced that the star underwent a series of very brief, non-periodic dimming events while it was being monitored by NASA’s Kepler space telescope, and no one could quite figure out what caused them.
A new study from Carnegie’s Josh Simon and Caltech’s Ben Montet has deepened the mystery.
There’s a mystery afoot in the constellation Cygnus, and it’s one we thought we had figured out.
The star known as KIC 8462852 made news a few months ago when its unusual pattern of dimming led some to speculate that intelligent life could be to blame — so-called “alien megastructures.” The accepted explanation of its odd behavior was a swarm of dusty comets, but a new analysis calls that into question. The mystery begins when the Kepler space telescope surveyed KIC 8462852 (about 1480 light years away) in its search for potential exoplanets.
It was never the most likely explanation, however, and the absence of short-wave infrared light around the star was seen as eliminating that possibility entirely.
KIC 8462852 or “Tabby’s star” has dimmed like this several times before, prompting some researchers to suggest that the megastructures of an advanced alien civilization might be blocking its light.
And now—based on new data from numerous telescopes—it’s doing it again.
An artist's impression of a partially complete Dyson Sphere.
Speculation was rife that an earlier version might account for changes in KIC 8462852's brightness.