Astronomers believe that an alien star could have recently streaked through the outer edges of our solar system some 70,000 years after it did so when humans and Neanderthals shared the Earth.
Three years ago, University of Rochester astronomer Eric Mamajek and his colleagues studying a binary stellar system named Scholz’s star, noticed that the star, which is just 20 light years away – a next-door neighbor by astronomical standards – was moving very slowly across the night sky, apparently moving away from our solar system.
Even though the chances of prehistoric humans bothering to notice a new red light appearing in the sky are pretty slim, Eric Mamajek and his colleagues believe that Scholz’s star actually left other evidence of its trek across the fringes of our solar system.
A new study, published in the May 2017 edition of the Monthly Notices of the Royal Astronomical Society, backs up Mamajek's theory.
Analyzing the paths of more than 300 small bodies in our solar system with hyperbolic orbits, the authors found that some of these bodies apparently originated in the direction of the constellation Gemini. This pattern squares nicely with the trajectory of Scholz's star.
Scientists believe that one interstellar voyager — the cigar-shaped asteroid Oumuamua, which passed through the solar system last year — was probably flung from a binary star system like Scholz's star.