ROCHESTER, N.Y., Sept. 15 (UPI) — Astronomers say a “cannibal” star is devouring a companion star and possibly creating a second generation of exoplanets from the resulting orbiting material.
Joel Kastner, a professor at Rochester Institute of Technology, says a variable star in the constellation of Pisces is not the young star it appears to be, but is more likely a billion-year-old red giant that has gobbled up another nearby star or planet, an institute release reported Tuesday.
The star’s extreme properties have puzzled astronomers since they first looked at it 15 years ago, and its conflicting characteristics have hampered efforts to classify it as either young or old.
Using data from NASA’s Chandra X-ray Observatory, researchers say they’ve confirmed the star is in fact in a class of old stars that have engaged in stellar cannibalism.
“These giant stars’ companions have fallen inside and spun them up,” Kastner says. “But we’ve never actually caught one in the act. Our working speculation is that we are observing the star right at the point at which it has swallowed its companion and hence formed a disk.”
The enigmatic star is probably about a billion years old and just entering the red giant stage in its life cycle in which it swells to digest its star or planet companion.
“It could be a small star or a large planet,” Kastner says of the cosmic victim. “We don’t know which it could be, but we’re very interested in finding out.”
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