It was in the year 2005 that NASA's scientists were attracted towards the star, officially titled KIC 8462852, and sometimes called Boyajian’s Star. While monitoring the F-type main-sequence star, NASA’s Kepler Space Telescope captured a series of rapid dimming events.
"We propose that the secular dimming behaviour is the result of the inspiral of a planetary body or bodies into KIC 8462852, which took place ~10 to 1e4 years ago", astronomers wrote in an April 2017 study.
"Up until this work, we had thought that the star's changes in brightness were only occurring in one direction - dimming", Simon explained.
The star has been observed having unusual dips in brightness, which do not characterize other normal stellar objects that are slightly more massive than the sun.
Located in the constellation Cygnus, approximately 1,280 light-years from Earth, KIC 8462852, also known as “Tabby’s Star” or “Boyajian’s Star”, exhibited strange fluctuations in brightness seen by the Kepler Space Telescope during its primary mission searching the region for exoplanets.
In 2016, Tabetha Boyajian of Louisiana State University at Baton Rouge led a study of the star, which resulted in it being unofficially nicknamed in her honour.
A new study using NASA's Spitzer and Swift missions, as well as the Belgian AstroLAB IRIS observatory, suggests that the cause of the dimming over long periods is likely an uneven dust cloud moving around the star. This discounts the "alien megastructure" notion and other exotic speculations.
The smoking gun: Researchers found less dimming in the infrared light from the star than in its ultraviolet light. Any object larger than dust particles would dim all wavelengths of light equally when passing in front of Tabby's Star.
"This pretty much rules out the alien megastructure theory, as that could not explain the wavelength-dependent dimming," said Huan Meng, who did the research as part of a postdoctoral fellowship at the University of Arizona. Meng, who graduated with a PhD from the UA's Lunar and Planetary Laboratory in 2014, is the lead author of the new study published in the Astrophysical Journal. "We suspect, instead, there is a cloud of dust orbiting the star with a roughly 700-day orbital period."
According to the study, it has been found that the dimming is caused by particles of dust, but it does not really specify the origin of the dust, which could be direct or indirect results of the planetary impact events.
It only explains the long-term dimming and not the sudden short-term dimming events.