Stellar encore: Dying star keeps coming back to life

CAPE CANAVERAL, Fla. — Death definitely becomes this star.

Astronomers reported Wednesday on a massive, distant star that exploded in 2014 — and also, apparently back in 1954. This is one supernova that refuses to bite the cosmic dust, confounding scientists who thought they knew how dying stars ticked.

The oft-erupting star is 500 million light-years away — one light-year is equal to 9.5 trillion kilometres — in the Big Bear constellation. It was discovered in 2014 and, at the time, resembled your basic supernova that was getting fainter.

But a few months later, astronomers at the Californiabased Las Cumbres Observatory saw it getting brighter. They’ve seen it grow faint, then bright, then faint again five times. They’ve even found past evidence of an explosion 60 years earlier at the same spot.

Supernovas typically fade over 100 days. This one is still going strong after 1,000 days, although it’s gradually fading.

The finding was published Wednesday in the journal Nature.

“It’s very surprising and very exciting,” said astrophysicist Iair Arcavi of the University of California, Santa Barbara who led the study. “We thought we’ve seen everything there is to see in supernovae after seeing so many of them, but you always get surprised by the universe. This one just really blew away everything we thought we understood about them.”

Scientists do not know whether this particular supernova is unique; it appears rare since no others have been detected.