An alien star flew by the Solar System and threw comets and asteroids off of their normal orbits at the time in our history when early humans and the Neanderthals were still walking on Earth.
The Scholz's Star
In 2015 study, astronomers revealed that the Scholz's star appears to have grazed our star system about 70,000 years ago. It approached the solar system five times closer than our current closest star, the Proxima Centauri.
A new study supported the findings of the 2015 analysis using a different type of evidence. Carlos de la Fuente Marcos, from the Complutense University of Madrid, and colleagues analyzed 339 solar system bodies whose paths through space are V-shaped instead of circular or elliptical.
The researchers said that the trajectory of some of these objects was influenced by the passage of the Scholz's star.
"The pronounced over-density appears projected in the direction of the constellation of Gemini, which fits the close encounter with Scholz's star," the researchers wrote in their study, which was published in the journal Monthly Notices of the Royal Astronomical Society: Letters.
Our Ancestors May Have Seen The Scholz's Star
The Scholz´s star is a binary system composed of a small red dwarf about 9 percent the mass of the sun, and a less bright and smaller brown dwarf.
At its closest approach, the Scholz's star would have been a 10th magnitude star, which means that it is 50 times too faint to be seen with the naked eye. Brief flares on the star, however, could have lit it up thousands of times brighter and it could have made the star potentially visible to our wandering ancestors, who had looked up the sky. At this time, modern humans were on the verge of migrating from Africa, and the now-extinct Neanderthals, have not yet died out.
"While the binary system was too dim to see with the naked eye in its quiescent state during its flyby of the solar system ~70 kya, flares by the M9.5 primary may have provided short-lived transients visible to our ancestors," Eric Mamajek, from the University of Rochester in New York, and colleagues wrote in their 2015 study.
Red Dot In The Sky
Carlos de la Fuente Marcos and his team said that the star likely appeared as a faint reddish light to those who saw it at the time it flew by our solar system.