Dimming caused by natural or extraterrestrial blockage
By Cazzy Lewchuk, Staff Writer
A recent paper published by the archive website arXiv has detailed the unusual behaviour that existed in light emissions of a star 1500 light years away. Detected by the Kepler Space Telescope, the star’s light has been observed to dim by up to 20 per cent between random observations over the last five years. Out of over 150,000 stars observed through algorithm and human efforts, none of them have been found to dim in light more than a percentage or two—except for one, known as KIC 8462852.
The blockage would have to be caused by an object roughly half the diameter of KIC 8462852, a star estimated to be 1.5x the size of the sun. This size makes the vast object far too vast to be a planet, leading to the question of what is causing this mysterious blocking. One possible, if somewhat radical explanation, involves the blocking object not being a natural phenomenon, but, instead, a structure built by intelligent extraterrestrial beings.
Such a megastructure has been hypothesized in both science fiction and astronomy. A civilization could be harnessing energy of the star through technology for its own advancement, in a concept known as a Dyson Sphere.
In an interview with The Atlantic, astronomer Jason 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.”
However, natural cosmic explanations are more likely to be causing the dimness, even if it is not yet understood. An investigation by Tabetha Boyajian of Yale University hypothesized that the blockage was caused by a broken-up icy comet expanding in gaseous clouds orbiting the star.
Boyajian’s published paper only focused on “natural scenarios,” but she is also reviewing other ones. Other explanations could include a planet-sized collision (similar to when Earth’s moon was formed), or a group of comets pulled into orbit by a neighbouring star.
Whether the behaviour is caused by a natural or intelligently-designed structure, it raises questions such as the whereabouts of radiation wavelengths emitted by the absorbance of a star’s light, which is currently undetected. Scientists are working on further observations of KIC 8462852 to detect reoccurrences of the behaviour. This will be done through Earth-ground telescopes. Boyajian has also partnered with Wright and the directors of the SETI project (Search for Extraterrestrial Intelligence) to monitor the area for artificial radio signals, another possible sign of intelligent life and technology.
Those hoping for proof of extraterrestrial intelligence shouldn’t get too excited—the most likely scenario is one of the cosmic phenomena already known to exist in our galaxy. However, all possible explanations warrant serious consideration and investigation, and only time will tell what the true cause is of KIC 8462852’s mystery.