The mysterious dimming of the Tabby's Star may not be due to an alien megastructure looping around it. Researchers of a new study suggest that the star may have eaten a nearby planet, which could explain why it erratically loses its brightness.
Erratic Dimming Of Tabby's Star
The brightness of stars periodically dips by about 1 percent, which can be attributed to a planet orbiting around it. Scientists, however, have been baffled by Tabby's star, more formally known as KIC 8462852 because of its erratic dips of up to 22 percent.
Scientists have proposed a range of possible reasons that could explain the star's sporadic blinking from swarms of orbiting comets to enormous extraterrestrial structures. Researchers of a study published in December suggest that internal stellar dynamics could also be responsible for the dimming of the star.
New Theory To Explain Bizarre Light Pattern Of Tabby's Star
Now, researchers propose another theory that may explain the bizarre light pattern of the star. Brian Metzger, from Columbia University in New York, and colleagues think that the star is just returning to its natural state after having a cosmic meal.
In a study set to be published in the Monthly Notices of the Royal Astronomical Society on Monday, the researchers suggest that KIC 8462852 may have gobbled up a planet between 200 and 10,000 years ago.
The researchers said that a star devouring one or more of its own planet may result in light fluctuation similar to that observed in Tabby's star.
How can the star's planet meal explain its mysterious light signal?
The researchers explained that if the Tabby's star ate a planet in the past, the planet's energy would have caused the star to temporarily brighten and then gradually dim to its original brightness.
The star would be brighter after devouring the planet, but once the burning was complete, it would go back to around its original brightness. The bigger the devoured planet was, the longer it would take the star to dim.
It is possible that what astronomers observed was KIC 8462852 during its post-planet consumption as it was dimming back to its normal state.
Clouds Of Debris Orbiting Tabby's Star
The planet could have also been ripped apart or had its moons stripped away when it fell into KIC 8462852. The event left clouds of debris orbiting the star in eccentric orbits. Whenever the debris passes between us and the star, it would block some of the starlight and make the star seem to blink. Astronomers hope to see signature of the planetary debris passing close to Tabby's star.
"The transient dimming events could then be due to obscuration by planetary debris from an earlier partial disruption of the same inspiraling bodies, or due to evaporation and out-gassing from a tidally detached moon system," the researchers wrote in their study.
"The dimming events could arise from a large number of bodies comet- or planetesimal-mass bodies placed onto high eccentricity orbits by the same mechanism responsible for driving the more massive planets into KIC 8462852."