'Alien Megastructure' Star Update: Scientists Dismiss Alien Construct Theory, Suggest Undiscovered Comets

Remember that faraway star, the one with the strange dimming effect, that set the internet on fire with speculation that the odd dip in brightness by the star could be the result of extraterrestrial engineers successfully constructing an "alien megastructure" around the star? Well, a new study posits that the strange dimming in star KIC 8462852 is not due to such an alien construct but to something far less exciting -- a conglomeration of occluding interstellar space junk.

International Business Times reported last week that KIC 8462852, which has been the center of much scrutiny and speculation since it was discovered that the star was undergoing an unexplainable sustained dimming, has been the target of yet another study attempting to explain the dimming phenomenon. Eliminating other offered explanations of the loss in brightness (including cometary swarms and an artificial energy collection array known as a Dyson sphere, which has been referred to as an "alien megastructure"), scientists Valeri Makarov from the U.S. Naval Observatory in Washington, D.C., and Alexey Goldin from Teza Technologies in Chicago have developed the idea that the dimming effect of KIC 8462852 is the result of an occluding cloud of space junk between the star and the observer (i.e., us humans) of "interstellar comets." In short, Makarov and Goldin have taken the swarm of comets idea and moved it from inside the planetary system to outside the system.

The two scientists also posit that there is another as yet undetected star, one in the same line of sight as KIC 8462852 (also known as Tabby's Star), that the comet swarm is occluding and dimming. They hypothesize that if such a star is dimming behind Tabby's Star, then it can only mean that the cause of the dimming effect exists outside the planetary system in interstellar space.

There seems to another problem with the study's hypothesis -- besides there being no evidence that a star behind KIC 8462852 exists. Interstellar comets have yet to be discovered.

Makarov told New Scientist, "Maybe interstellar space is full of free-floating comets. But try to find them! They are dark and cold, and travelling from nowhere to nowhere, basically, forever."

Alien star occlusion
Alien star could be dimmed by a swarm of comets and space junk. [Image by Johan Swanepoel / Shutterstock]

Interstellar space is a vast emptiness that could very well hold Makarov's missing comets. It is known that rogue planets drift through interstellar space, so the idea of a "comet swarm" existing somewhere -- or, for Makarov and Goldin's hypothesis, outside the planetary system of Tabby's Star -- is not altogether outlandish.

The paper also has a glaring omission, according to the International Business Times. It does not address the 20 percent dip that scientists have detected in KIC 8462852's brightness over the last century.

In short, proponents of the alien megastructure argument have lost no ground with regard to the latest theory. As yet, the paper by Makarov and Goldin has not been peer reviewed.

Alien star with occluding material
Alien star KIC 8462852 could be hosting a Dyson sphere to help harness its energy. [Image by zeber / Shitterstock]

"If this is right, then that conclusion is dead on," Jason Wright of Pennsylvania State University said of the study. Wright originally postulated the alien megastructure theory to explain Tabby's Star's dimming. He also noted that if a second star can be detected and is found to undergo the same dimming process, the Makarov and Goldin position will be further strengthened. Wright pointed out, however, that a cometary swarm close enough to occlude a star would not technically be an interstellar one.

Wright told New Scientist that he, too, had come to believe that only an interstellar cloud occluding Tabby's Star could account for its century-long dimming. Still, finding such a cloud was going to prove difficult.

Makarov thinks that proof of the new theory might have to wait a decade or so until the second star moves far enough away from KIC 8462852 to be detected. Until then, those holding out for an alien presence in the faraway system can still hope that a dimming star is proof that not only is there alien life in the cosmos but that it is intelligent and technologically advanced.

[Featured Image by Marc Ward / Shutterstock]