By Lucas Wilson
Are we alone? – Perhaps the most profound question humans can ask. However, an anomalous phenomenon observed near Tabby’s star could finally answer that controversial question.
In September 2015, a team of civilian scientists funded by the Planet Hunters project observed an unusual phenomenon: fluctuations in the brightness of a star known colloquially as Tabby’s Star and officially as KIC 8462852.
The discovery of this anomaly drew the attention of the National Aeronautics and Space Administration (NASA), who, in an effort to attain more information, focused the highly sensitive Kepler Space Telescope on the star. The telescope showed light curves (non-periodic changes in the luminosity of a star) in the light emitted by the star.
The most obvious explanation for this unusual behaviour is that the star simply has a variable brightness, however, due to the type of star that Tabby’s star is (that is one whose brightness cannot be modified), this theory is impossible. Furthermore, the change in brightness of the star is only visible in certain parts of the star. This offers further evidence that variable brightness does not cause this behaviour, therefore, it is likely that these light curves are caused by unidentified objects near the star.
There are many theories about what these objects might be, ranging from large comets orbiting the star, to an alien superstructure that has been extracting a vast amount of energy from the star and as a result its overall brightness decreases.
An additional possibility is that a giant “alien megastructure”, similar to a Dyson sphere, had been constructed in its orbit to absorb radiation from the star and convert it into energy. This theory was made famous by Jason Wright et al, an astronomer at Pennsylvania State University; he believes that aliens constructed the structure in an effort to fuel their interstellar energy needs. However, a recent survey of the star by SETI (Search for Extraterrestrial Intelligence) has found that no artificial signals were being emitted by the star, thus making this theory highly unlikely.
On the other hand, scientist Bradley Schaefer has theorized that this anomalous behaviour could be caused by debris that is in orbit around the star. This debris could alter the brightness in a similar way to that of the observations recorded. Despite this, a survey conducted by NASA’s WISE space telescope found that there is not an excess amount of infrared radiation, an indication of large stellar debris, near the star and therefore this theory is, again, highly improbable.
Another theory is that it is possible that matter from comets and other large objects have accreted in orbit around the star, which may have temporarily blocked out the light coming from the star (however, this only partially explains the phenomena). This could cause the anomalous behaviour observed. But, it would not account for the fact that measurements done by the star’s discoverer, Tabetha S. Boyajian, show that the star is very old. Because of this, it should have already accreted all of the matter near to it and thus making this theory impossible.
Ultimately, there are many theories as to what these extremely anomalous light fluctuations are caused by; ranging from large amounts of matter accumulating around the star to an alien megastructure extracting vast swathes of energy. In the end, we may never know without further investigation of the star, and the space around it.
The information presented in this article does not necessarily reflect the views or beliefs of The Update. We are reporting either the facts or opinions held by third parties related to the subject of the article.
 Variable brightness stars are fairly common.
 A Dyson sphere is a large, artificial, satellite that was first theorized by Olaf Stapleton and popularized by Freeman Dyson as a means of capturing a huge amount of energy from a star.