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Planet-eating star shows the Solar System's future

It'll thankfully take billions of years before our sun starts eating our solar system's planets.

Gabi Perez / Instituto de Astrofísica de Canarias

Some 300 light-years away, there's a star that's very similar to our own, and it shows that our sun could devour its planets that get a wee bit too close. A team of astronomers, who've been monitoring star HIP68468 for years, have revealed the star's planet-ingesting past in a new study. What clued them in is HIP68468's lithium content, which is four times what you'd expect from a star that's six billion years old. Stars typically burn through their lithium content over time, so the element's abundance coupled with the presence of heat-resistant metals commonly found in rocky worlds can only be explained by the consumption of planets.

"It's as if we saw a cat sitting next to a bird cage," Yale University professor Debra Fischer (who's not involved with the study) said. "If there are yellow feathers sticking out of the cat's mouth, it's a good bet that the cat swallowed a canary." The team saw enough lithium and rocky planet material on HIP68468 to form six Earths. That said, the scientists believe it still has at least a couple of planets left: one is a supersized Neptune, while the other is a super-Earth.

Since the star is very similar to our own, this discovery shows us how solar systems like ours could evolve over time. Before you panic, take note that we're not getting sucked into an enormous ball of fire anytime soon. Based on the team's computer simulations, it will take billions of years of gravitational tugs and pulls before our sun starts gobbling up its planets. Besides, Mercury and Venus are bound to go first.