This led to a flurry of studies and articles that sought to offer entirely natural explanations for what has been observed. Even SETI weighed in, indicating that they would begin searching for indications of radio signals coming this mysterious star. But after two years and multiple studies that offer explanations other an alien Dyson Sphere (or some other type of megastructure), the star is at it again!

The first indications that the star was dimming again were reported late last month by the Fairborn Observatory in Arizona. The robotic telescope spotted what might be a dip in brightness on April 24th, 2017. Within a week, the brightness returned to normal levels, but the event (known as “Event 1” in the star’s light curve, shown below) caught the interest of astronomers around the world.

Then on May 18th, a more significant drop began, which prompted the observatory’s scientists to put out the call to observatories around the world to begin turning their telescopes to Tabby’s Star. According to the alert issued by the Observatory, the star had already dimmed by 2% after just one night of observation. As soon as the Sun set in their respective regions, observatories around the world began monitoring the star and recording its light curve.

This included the Center of Excellence for Information Systems Engineering and Management (a research laboratory at the University of Tennessee), the W.M. Keck Observatory in Manau Kea, the American Association of Variable Star Observers (AAVSO), and the MMT Observatory in Arizona (which has been providing additional spectroscopy).

The Las Cumbres Observatory Global Telescope Network (LCOGT), which was regularly monitoring the star already, also joined the observation party. While this was happening, Tabetha Boyajian (for whom the star is named) called Jason Wright – an associate professor of astronomy at Pennsylvania State University – to tell him the news. Wright received the call on Friday, May 19th, at 4 a.m., at which point, he was told that the dimming had reached 3%.