The “Alien Megastructure” star is acting up again, and scientists around the world are puzzled. On Thursday morning, astronomer Matt Muterspaugh noticed something different with KIC 8462852, also known as Tabby’s Star or the Alien Megastructure star.
Muterspaugh looked at telescope data taken from the night before and saw that the star’s light had dimmed significantly. He contacted other astronomers who were also observing it, and by the next morning, the star had dimmed even more.
That day, scientists realised the Alien Megastructure star was acting strange again, and they set out to discover what was going on with it.
Tabby’s Star was first sighted in data from the Kepler spacecraft
Astronomers around the world are now trying to figure out what is happening to the star, and telescopes were fixed on KIC 8462852 throughout the weekend.
“As far as I can tell, every telescope that can look at it right now is looking at it right now,” said Muterspaugh, a professor at Tennessee State University, according to The Verge.
KIC 8462852 was dubbed Tabby’s Star after Tabetha Boyajian, an astronomer at Louisiana State University, first saw the odd star a few years ago after looking through archive data from Kepler, the NASA spacecraft in charge of looking for planets outside of our Solar System. Boyajian was part of a science project called Planet Hunters, which allowed volunteers to analyse Kepler data to look for planets, and they alerted her to the strange star.
“Our users flagged it to be something really interesting,” told Boyajian to The Verge. “They came to the science team and asked, ‘What is this? That’s not a planet clearly.’”
The Kepler data showed that the star experienced some extreme fluctuations in brightness, more than a passing planet could experience. They noted that the star’s light dimmed by 20 percent at one point, evidencing a never-before-seen irregularity with a star.
In late 2015, an astronomer from Penn State, Jason Wright, suggested that the dips were caused because large megastructures created by an alien civilisation were orbiting around the star, which would explain the weird changes. Wright said at the time that aliens should always be the last hypothesis you consider, but that the phenomenon looked like something you would expect an alien civilisation to build. After Wright’s hypothesis, the star also became known as the “alien megastructure” star.
Astronomers are seeking natural explanation to Alien Megastructure Star’s light dips
Despite Wright’s theory, scientists were still looking a natural explanation for the dips, and some suggested that a massive swarm of giant comets periodically orbits the star. Boyajian said that they were stuck in a spot where they couldn’t do anything, as they had all the data but to learn something new they needed to catch the star in action again. The problem is that the star is very unpredictable, the fluctuations aren’t repetitive, and they don’t seem to follow any pattern, making it hard for the scientists to learn when the star would act strange again.
“Things that change the brightness of a star happen in a very regular pattern,” said Muterspaugh, according to The Verge. “And from what we can tell so far, [this star] is not periodic. We cannot predict when it happens, and that makes it very weird.”
Given the star’s unpredictability, astronomers have been looking at Tabby’s Star every day since they learn of its dimming conduct. Boyajian even started a Kickstarter campaign called “Where’s the Flux?” to have funds to secure enough telescope time to view the star. The campaign raised more than $100,000, which allowed Boyajian and other astronomers to set up a year-long observation program through the Las Cumbres Observatory, which owns telescopes stationed around the world. Muterspaugh also set up an observation campaign with the robotic telescopes at the Fairborn Observatory in Arizona, and one of them was fixed permanently on the star. Astronomers didn’t notice any weird activity in the star for the last years.
All theories are still possible, including the alien megastructure
However, on April 24, data from Fairborn showed that the star had dimmed a little, and although it wasn’t enough for astronomers to think the star was acting up again, they remained on guard. Then, nearly a month later, the star dimmed again in a significant way. Now, astronomers have the opportunity to use their entire arsenal of telescopes to observe the Alien Megastructure stars and the dips that occur in it.
Boyajian said that the response from the science community has been overwhelming, and everyone right now is seeking to help out and document the changes with the star.
Every theory regarding Tabby’s Star is on the table, including the alien megastructure one. Muterspaugh said that they would hate if that theory turns out to be true because it would be a pretty significant thing. He noted that it would be “awesome”, but as scientists, they hope there’s a natural explanation.