More than a quarter of stars like our sun could eat their own planets

Astronomers say they have strong evidence that up to a quarter of all sun-like stars could have a nasty habit of preparing massive meals from planets in their system. But do not worry. This turns out to be good news for our chances of becoming a stellar snack, and might even come in handy in the search for another Earth elsewhere in the cosmos.

In recent years, as scientists have increasingly studied binary star systems, in which two sister stars revolve around each other, they found these pairings to be more different than expected. In particular, the chemical compositions of the two stars are often different from each other. This contradicts the theoretical assumption that each was formed from the same primordial stew and therefore the duo should be more or less identical in the chemical sense.

An international team of astronomers spanning four continents studied a sample of 107 binary pairs of stars similar to the sun. They discovered that 33 of the binaries were “chemically abnormal” with high levels of iron that don’t quite match the current understanding of star evolution. The two main potential explanations for this stellar weirdness are that twin stars can sort of be made up of different things from birth, or that one of the stars engulfs a planet or three later. The team says their work is a strong indication that the latter option is more likely.

“The observations are consistent with a scenario in which stars are polluted with Earth-like material accumulated from their planetary systems,” reads an article published in In Nature Astronomy by the group, led by Lorenzo Spina of the Italian National Observatory of Padua.

Before you worry about the sun showing signs of hunger, Spina and her colleagues say this revelation is actually good news for the planets in our own solar system, which has always been remarkably stable. Our sun shows little sign of eating Mercury anytime soon, at least not before it turns a red supergiant and expands to engulf most of the inner solar system, including Earth.

But it’s probably at least a billion years away, so relax.

Meanwhile, the new research could help find Earth-like planets that may harbor life around other stars. Scientists believe that looking for signs that a star is a world swallower might be a way to mark it on the list of places worth looking for, as such systems are less likely to be stable enough. for life to evolve.

“Therefore, we now have a potential ‘upstream’ method for identifying Sun-like stars that are less likely to host Earth-like planets, which could be useful as a criterion for planet searches,” reads -on in the document.

Looks like we’ve been lucky enough to live next door to a star who’s never been hungry. At least not yet.

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