Red Dwarf Scholz Closest to Cruise Through Solar System 70,000 Years Ago

The solar system had an unusual visitor about 70,000 years ago, which experts have termed as a rare event and close shave.

According to BBC, the solar system was visited by a red dwarf, low mass star, known as Scholz's star which swept pass the outer fringes of the solar system through an area known as Oort Cloud. The cruising of the star through the solar system was surprising to scientists as its nearest approach was closer than the closest star to the Sun, Proxima Centauri which is 4.2 light years away. Scholz's star is now about 20 light years away.

Researchers analysed the star's trajectory to determine its past course. They found that the red dwarf was not alone during its journey. It was accompanied by an orbiting brown dwarf. The binary system carried a risk of upsetting comets in the Oort Cloud which could have entered the inner solar system.

"Most stars this nearby show much larger tangential motion. The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar system, or it had 'recently' come close to the solar system and was moving away. Sure enough, the radial velocity measurements were consistent with it running away from the Sun's vicinity - and we realized it must have had a close flyby in the past," study's lead author Eric Mamajek at University of Rochester in a news release.

Mamajek also told NBC News that another star HIP 85605 which is expected to pass through the solar system about 240,000 years later, will not come as close as Scholz's star.