Our sun has had close encounters with other stars in the past, and it’s due for a dangerously close one in the not-so-distant future. 

Every 50,000 years or so, a nomadic star pᴀsses near our solar system. Most brush by without incident. But, every once in a while, one comes so close that it gains a prominent place in Earth’s night sky, as well as knocks distant comets loose from their orbits. 

The most famous of these stellar interlopers is called Scholz’s Star. This small binary star system was discovered in 2013. Its orbital path indicated that, about 70,000 years ago, it pᴀssed through the Oort Cloud, the extended sphere of icy bodies that surrounds the fringes of our solar system. 

Some astronomers even think Scholz’s Star could have sent some of these objects tumbling into the inner solar system when it pᴀssed. However, Scholz’s Star is relatively small and rapidly moving, which should have minimized its effect on the solar system. 

But in recent years, scientists have been finding that these kinds of encounters happen far more often than once expected. Scholz’s Star wasn’t the first flyby, and it won’t be the last. In fact, we’re on track for a much more dramatic close encounter in the not-too-distant future.

Astronomers discovered nearly 700 stars that will pᴀss within 15 light-years of our solar system over just the next 15 million years. However, the vast majority of close encounters have yet to be discovered, but they suspect roughly 20 stars should pᴀss within just a couple light-years of us every million years.

Research paper