Back in the summer of 2016, astronomers observed a star located 2,500 light-years away in the Cygnus constellation spark as if getting ready to blow off into a violent supernova.
The following day, though, the star got back to its usual brightness with no fuss and no explosion. Within a few weeks, however, the cycle repeated yet again: the object began to brighten suddenly, then went dull within a day. Throughout 2017, the behavior continued, and it repeated five different times within 500 days.
“This was a very unusual behavior,” Łukasz Wyrzykowski, an astronomer who observed the peculiar star at the Astronomical Observatory of the University of Warsaw, Poland, said in a statement. “Hardly any type of supernova or other star does this.”
Invisible Binary Systems Put Out a Show
Now, as per a research published on January 21st in the journal Astronomy and Astrophysics, it has been proved that the peculiar cosmic object, dubbed Gaia16aye, was actually not doing anything odd. Rather, the study authors stated, it seems like there is a set of intrusive binary stars that are warping space-time before Gaia16aye, producing a field of cosmic magnifying glasses. These glasses enhance the star’s light each time it passes behind them, and the binary system was effectively not visible from Earth.
The stellar magnifying impact, where gigantic cosmic bodies appear to bend space-time around them, is known as ‘gravitational lensing’ and was mentioned in Albert Einstein‘s theory of general relativity. Researchers have since utilized the event to observe more attentively some of the most ancient stars, galaxies, and bodies in the Universe, but the impact can also unveil the characteristics of much closer, fainter objects.
For instance, the binary system that’s been impacting Gaia16aye: while the pair are completely invisible to us, the power and regularity of their gravitational lensing enabled the scientists to go backward and discover ‘basically everything’ about them, the paper co-author, Przemek Mróz, a postdoctoral scholar at the California Institute of Technology, stated.
The Milky Way Could Host Millions of Such Events
The team of researchers determined that in order to generate the regular, all-day brightening of the star, the binary system must be producing not one, but numerous series of magnification, which are also known as gravitational microlensing.
That means these objects are most probably a duo of small, red dwarfs about 0.57 and 0.36 times the weight of our Sun, located at a distance of about twice the length between the Earth and the Sun, the study authors stated.
If microlensing occurrences like this one can unveil invisible objects, such events may also be about to expose even rarer and more enigmatic cosmic spectacles. Hopefully, the scientists said, that will also contain black holes, which are usually identifiable only when they are consuming matter found in their vicinity and evicting jets of gassy light.
According to the researchers, our galaxy, the Milky Way, could also be harboring millions of individual black holes at a considerable distance from any stars in our vicinity to generate such a light show, and gravitational lensing could be the main element that can contribute in detecting them.