The Kepler Space Telescope observed light coming from tens of thousands of stars during its operational life. The Kepler ascertained the existence of hundreds of exoplanets by measuring periodic dips in the brightness of certain stars that indicate planets orbiting them. The Atlantic published a story on Tuesday about one such star, KIC 8462852, about 1,500 light-years from Earth. The fluctuations of light output from that star suggest that something odd is present in that distant solar system. Some are whispering that the something odd are alien artifacts.
The Planet Hunters, a group of citizen scientists who are looking at Kepler data to try to find more exoplanets, noticed something about KIC 8462852 and its light pattern
“The light pattern suggests there is a big mess of matter circling the star, in tight formation. That would be expected if the star were young. When our solar system first formed, four and a half billion years ago, a messy disk of dust and debris surrounded the sun, before gravity organized it into planets, and rings of rock and ice.”
That finding in and of itself would have been interesting. But there was only one problem. KIC 8462852 is not a young star.
“And yet, there is this mess of objects circling it. A mess big enough to block a substantial number of photons that would have otherwise beamed into the tube of the Kepler Space Telescope. If blind nature deposited this mess around the star, it must have done so recently. Otherwise, it would be gone by now. Gravity would have consolidated it, or it would have been sucked into the star and swallowed, after a brief fiery splash.”
A recent paper outlines a number of natural explanations, including an instrument malfunction, a planetary calamity that created a recent asteroid belt, or a close encounter with another star that pulled a swarm of comets closer to KIC 8462852. Scientists believe that the latter is the most likely explanation, albeit one that would seem highly rare and coincidental.
An alternate explanation exists.
“Jason Wright, an astronomer from Penn State University, is set to publish an alternative interpretation of the light pattern. SETI researchers have long suggested that we might be able to detect distant extraterrestrial civilizations, by looking for enormous technological artifacts orbiting other stars. Wright and his co-authors say the unusual star’s light pattern is consistent with a ‘swarm of megastructures,’ perhaps stellar-light collectors, technology designed to catch energy from the star.”
Wright and the scientists at Planet Hunters have proposed that a radio telescope be pointed at KIC 8462852 to see if it is emitting radio waves that suggest that a technological civilization exists in that distant star system. The observation would be followed up by another by the Very Large Array (VLA) in New Mexico.
At this point, it is too soon to make an announcement that aliens have been detected 1,500 light years away. Indeed, chances are the explanation that the light pattern is caused by nature. But, if radio signals are detected, the event would be world changing.
Mark R. Whittington is the author of Why is it so Hard to Go Back to the Moon? and The Man from Mars: The Asteroid Mining Caper