TECH
19/02/2015 09:58 GMT | Updated 19/02/2015 11:59 GMT

Alien Star Passed Through Solar System Just 70,000 Years Ago

An ancient, alien star passed through our solar system just 70,000 years ago, astronomers have discovered.

The rogue star came five times closer to Earth than Proxima Centauri, the nearest star to our solar system today which is about 4.2 light years from Earth.

The red dwarf star - Scholz’s Star - passed through the outer reaches of the solar system accompanied by a brown dwarf “failed” star, and may have even been responsible for flinging a comet or two towards our sun.

The incredible finding was announced in the Astrophysical Journal Letters.

brown dwarf

Eric Mamajek at the University of Rochester, who led the study, said that Scholz’s Star passed within 0.8 light years of our sun, passing through the ‘Oort Cloud’ region in which trillions of comets form a rock shell around the Solar system.

To work out the path of the star - which is now 20 light years away - the researchers needed to know how its distance had changed in relation to the Sun, and how it had moved across the sky.

Their results indicated it was either moving away from the Sun, or heading straight for us. The good news is that it was the former, meaning that it has already made its close encounter and is now heading off into deep space.

Dr Mamajek told the BBC that the star probably did not trigger a “significant 'comet shower'" -- both the star and its companion are relatively low in mass -- but might have disturbed a few comets.

The team said that stars probably come close to our solar system once every 100,000 years, with closer passes much rarer at once every few million years.

Fringe theories have pondered whether a so-called ‘nemesis’ star could cause regular mass extinctions on Earth by passing close to the inner solar system — but fortunately we currently have no good evidence that something so catastrophic has actually occurred.