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MIT and Harvard researchers say they’ve observed for the first time a star swallowing a planet

This artist’s impression shows a doomed planet skimming the surface of its star.K. Miller/R. Hurt (Caltech/IPAC)

For the first time, scientists have observed a star swallowing a planet, a preview of what will happen to the Earth 5 billion years from now, the Massachusetts Institute of Technology said Wednesday.

The discovery was made by scientists from MIT, Harvard University, the California Institute of Technology, and other institutions. The research was described in a study in the journal Nature.

Lead author Kishalay De, a postdoctoral student in MIT’s Kavli Institute for Astrophysics and Space Research, said in a video news conference that scientists have believed that stars eventually swallow their nearby planets as they evolve, but “what we’ve never really seen is a star in this act of engulfment itself and that was sort of the missing piece in this entire puzzle.”


As a star nears the end of its life, it expands, swallowing any matter — including planets — in its vicinity, MIT said.

That’s what scientists believe happened in our galaxy near the constellation Aquila about 12,000 light-years away, MIT said. A hot, Jupiter-sized planet spiraled closer and was dragged into a dying star’s ballooning atmosphere and into its core.

A similar thing is expected to happen to the Earth in another 5 billion years, when the sun is expected to burn up the solar system’s inner planets, MIT said.

“In some ways, it’s a bit poetic in that, you know, this is going to be the final fate of the Earth - five billion years from now, fortunately,” De said.

The discovery came after scientists scrutinized “a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission,” the study’s abstract said. The scientists deduced that what they saw could only have been produced by one event: a star engulfing a nearby planet, MIT said.

“We weren’t quite looking for this,” said De. “We were looking for similar things but not quite this. And, like a lot of discoveries in science, this happened to be an accidental discovery that really opened our eyes to a new type of phenomenon.”


“This is just spectacular,” co-author Mansi Kasliwal, a professor of astronomy at Caltech, said in a statement from her university. “We are still amazed that we caught a star in the act of ingesting its planet.”

MIT said the discovery was made possible by observations from Caltech’s Palomar Observatory in California, the Keck Observatory in Hawaii, and NASA’s infrared space telescope, NEOWISE.

“We never thought we were going to see a planet in the process of digestion. I think it’s a great discovery,” said astrophysicist Enrico Ramirez-Ruiz, who was not involved in the study.

Ramirez-Ruiz, a professor at the University of California Santa Cruz, said scientists knew that the process happened, but they thought “it was going to be incredibly difficult to see it. … Either we got incredibly lucky or the rate of these events is higher than we expected.”

“Wow! That is my first reaction,” Amanda Karakas, an astrophysicist at Monash University in Australia who was not involved in the study, said in an e-mail to The Washington Post. “It certainly provides clues as to what will happen to the planets in our solar system and the Earth, many years from now.”

The findings are “very plausible,” Carole Haswell, an astrophysicist at Britain’s Open University, who was not involved in the study, told The Associated Press. Haswell led a team in 2010 that used the Hubble Space Telescope to identify the star WASP-12 in the process of eating its planet.


“This is a different sort of eating. This star gobbled a whole planet in one gulp,” Haswell said in an email. “In contrast, WASP-12 b and the other hot Jupiters we have previously studied are being delicately licked and nibbled.”

Material from Globe wire services was used in this report.

Martin Finucane can be reached at martin.finucane@globe.com.