Have Citizen Scientists Found an Alien Megastructure?
A distant star whose observed brightness fluctuates in ways that are difficult to explain has scientists and SETI (Search for Extra Terrestrial Intelligence) enthusiasts openly talking about a possible artificial origin of the star’s luminosity fluctuations. The data are compatible with the possible presence of an alien super-civilization around the star KIC 8462852, located in the constellation Cygnus at approximately 1,481 light years from the Earth.
KIC 8462852 was discovered through Planet Hunters, a citizen science program launched at Yale University in 2010. Using data from the Kepler Space Telescope, volunteer citizen scientists look for planets by monitoring variations in the brightness levels of about 150,000 stars. A variation in the observed brightness of a star could, in fact, be caused by a planet passing in front of the star. So far, several planets around other stars have been first spotted by Planet Hunters, and then confirmed.
An article accepted for publication in the Monthly Notices of the Royal Astronomical Society reports that KIC 8462852 was observed to undergo irregularly shaped, aperiodic dips in flux down to below the 20 percent level. A freely accessible version of the paper titled “Planet Hunters X. KIC 8462852 – Where’s the Flux?” is available from arXiv.
It’s important to note that even a very large planet like Jupiter would only cause a drop of about one percent in the luminosity of its parent star, nowhere near the more than 20 percent change observed for KIC 8462852. The article outlines several candidate explanations of the observed results. “We describe various scenarios to explain the mysterious events in the Kepler light curve, most of which have problems explaining the data in hand,” note the scientists. “We conclude that the scenario most consistent with the data is the passage of a family of exocomet fragments, all of which are associated with a single previous breakup event.” The scientists add that future observations are needed to make sense of the data.
A Swarm of Megastructures Built to Catch Energy From the Star
“We’d never seen anything like this star,” says first author Tabetha Boyajian, a postdoc at Yale, The Atlantic reports. “It was really weird.”
If a simple natural interpretation of the data is difficult to find, perhaps we should consider the possibility of a very large “megastructure” built by an advanced alien civilization around KIC 8462852. In particular, scientists are imagining a “Dyson sphere” or ring (shown in the right picture) – a megastructure that completely encompasses a star and hence captures most or all of its power output. A Dyson sphere could be built by a civilization that, having reached Type II in the “Kardashev Scale” of technological advancement, is able to harness all the energy of its star.
Jason Wright, an assistant professor of astronomy and astrophysics at Penn State University, suggests that the unusual star’s light pattern is consistent with a “swarm of megastructures,” perhaps stellar-light collectors, technology that’s designed to catch energy from the star. “When [Boyajian] showed me the data, I was fascinated by how crazy it looked,” Wright said.
Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilization to build.
The Washington Post reports that Boyajian, Wright and Andrew Siemion, the director of the SETI Research Center at the University of California, Berkeley, are working on getting access to large radio telescopes able to detect radio waves sent from an hypothetical alien civilization around KIC 8462852.
Images from Wikimedia Commons.