It’s being called a very close call, at least in astronomical terms.
An international team of astronomers said Tuesday the star passed through the solar system’s distant cloud of comets, known as the Oort Cloud.
The research indicates that 70,000 years ago a dim star passed within a mere 8 trillion kilometers (5 trillion miles) of our solar system.
That’s about one-fifth the distance from the solar system to Proxima Centauri, the star that is currently our system’s closest stellar neighbor, and the closest that any star has ever come to our system.
No other star is known to have ever approached our solar system this close — five times closer than the current closest star, Proxima Centauri, said the team of researchers from the US, Europe and South America.
Using spectrographs and large telescopes in South Africa and Chile, researchers were able to go back in time and reconstruct its trajectory by calculating its speed.
They were also able to determine that it is now heading away from our solar system.
There are trillions of comets in the Oort cloud and likely some of them were perturbed by this object,” Mamajek told BBC News.
“But so far it seems unlikely that this star actually triggered a significant ‘comet shower’.”
Analysis of the trajectory of this recently discovered star suggests it passed roughly 0.8 light years from our solar system.
The star is now 20 light years away, said Eric Mamajek, from the University of Rochester in New York and lead author of the study.
Their study was published in the journal Astrophysical Journal Letters.