The unusual behavior of the star, located 1,480 light years from Earth, could indicate the presence of an alien civilization.
Astronomers proposed this hypothesis based on observations using the Kepler space observatory. Now they plan to study the strange behavior of the star using the directional signal of a powerful radio telescope. The preliminary results of the study are presented in the arXiv preprint journal and briefly reported by The Atlantic.
The Kepler Observatory is designed to search for exoplanets (planets outside the solar system) by the transit method - by the drop in the luminosity of a star during the passage of a planet in front of its disk. This usually causes the light to dim for several hours or days, and at regular intervals.
However, invisible to the naked eye, KIC 8462852 (a single star in the constellation Cygnus) turned out to be an exception: its luminosity fell by 80 percent, and remained at such a low level for various periods of time (from five to 80 days).
Professional and amateur astronomers who took part in the processing of data from Kepler (it was they who first drew attention to the anomalous behavior of the star in 2011) conducted a thorough analysis of the information and ruled out the possibility of signal distortion or problems with the telescope.
Photo: NASA
The features of the light indicate that many objects are circling close to each other around the star. This phenomenon often occurs in young stars surrounded by a disk of cosmic dust and large debris (over time, the forces of gravity force this substance to gather into planets, or it is sucked into a star). However, KIC 8462852 is not a young star.
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Scientists have rejected several more hypotheses (asteroid belt, planetary collision similar to the one that created the Moon), and now the only realistic scenario is the passage of another star near KIC 8462852, resulting in a whole cloud of comets in its orbit. The disintegration of these celestial bodies as they rotate in the star's orbit may explain the irregular scintillation. However, such an event should have happened only a few millennia ago (an insignificant period by cosmic standards), which makes it extremely unlikely.
Tabetha Boyajian, lead author of the study, considers another scenario. The blinking of KIC 8462852 may indicate the Dyson Sphere - a collection of giant objects (for example, light collectors) that a highly developed extraterrestrial civilization built to accumulate the energy of its star.
"Aliens should always be the very last hypothesis to consider, but it looks like what you'd expect from an extraterrestrial civilization," said astronomer Jason Wright of Pennsylvania State University.
Boyajian, Wright and director of the SETI Research Center, Andrew Siemion, are now applying to target KIC 8462852 with a radio telescope to see if the star is emitting radio waves at frequencies characteristic of technological activities.
If the first observations detect significant radiation in this range, the star will be tracked using the Very Large Array, one of the largest radio telescopes in the world. Work should start in January 2016.