In a galactic first, a star swallows the planet in one gulp
CAPE CANAVERAL, Fla. (AP) — For the first time, scientists have caught a star swallowing a planet — not just a nibble or bite, but one big gulp.
Astronomers on Wednesday reported their sightings of what appeared to be a gas giant the size of Jupiter or larger being eaten by its star. The sun-like star had been swelling with age for centuries, eventually growing so large that it engulfed the planet in a nearby orbit.
It’s a bleak preview of what will happen to Earth when our sun turns into a red giant and swallows up the four inner planets.
“If it’s any consolation, this will happen in about 5 billion years,” said study co-author Morgan MacLeod of the Harvard-Smithsonian Center for Astrophysics.
This galactic feast took place between 10,000 and 15,000 years ago near the constellation Aquila when the star was about 10 billion years old. As the planet passed through the stellar hatch, there was a rapid hot burst of light followed by a prolonged stream of dust that shone brightly in cold infrared energy, the researchers said.
While there had been previous signs of other stars nibbling on planets and their aftermath from their digestion, this was the first time the swallow itself had been observed, according to the study appearing in the journal Nature.
Massachusetts Institute of Technology researcher Kishalay De saw the 2020 light burst while viewing sky scans taken by the California Institute of Technology’s Palomar Observatory. Additional observations and data analysis were needed to unravel the mystery: Instead of a star swallowing its companion star, it had devoured its planet.
Given a star’s lifespan of billions of years, the swallow itself was quite short — essentially in one fell swoop, said Caltech’s Mansi Kasliwal, who was part of the study.
The findings are “highly plausible,” said Carole Haswell, an astrophysicist at Britain’s Open University, who had no role in the study. Haswell led a team in 2010 that used the Hubble Space Telescope to identify the star WASP-12 as it consumed its planet.
“This is a different kind of food. This star swallowed an entire planet in one gulp,” Haswell said in an email. “WASP-12 b and the other hot Jupiters we’ve studied before, on the other hand, are subtly licked and nibbled.”
Astronomers don’t know if there are other planets orbiting this star at a safer distance. If so, De said they may have thousands of years before they become the star’s second or third orbit.
Now that they know what to look for, the researchers will be on the lookout for more cosmic gulps. They suspect that thousands of planets around other stars will suffer the same fate as this one and eventually our solar system as well.
“Everything we see around us, all the things we built around us, all of this will be gone in a flash,” De said.
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