Astronomers thought they knew how dying stars behaved—until one supernova refused to bite the cosmic dust. The massive, distant star exploded in 2014—and also, apparently, back in 1954.
The oft-erupting star is 500 million light-years away, in the direction of the Ursa Major (Big Bear) constellation. At the time it was discovered in 2014, it resembled a typical supernova that was getting fainter.
But a few months later, astronomers at the California-based Las Cumbres Observatory saw it brighten again. They’ve watched it grow faint, and then bright, and then faint five times. They’ve also found 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. The report describing the surprising pattern was published in November in the science journal Nature.
Astrophysicist Iair Arcavi of the University of California, Santa Barbara, called the phenomenon “very exciting…We thought we’ve seen everything there is to see in supernovae…but you always get surprised by the universe. This one just really blew away everything we thought we understood.”
The supernova is officially known as iPTF14hls. It is believed to have been a star up to 100 times more massive than our Sun. It could be the biggest stellar explosion ever observed, which might explain its death-defying peculiarity.
It could be multiple explosions occurring so frequently that they run into one another. Or perhaps it is a single explosion that repeatedly gets brighter and fainter, though scientists don’t know how this happens. One possibility is that a massive explosion blew away the star’s outer layers. The hot core may have been left intact enough to repeat the entire process.
Harvard University’s astronomy chairman, Avi Loeb, has another theory. He speculates a black hole might be at the center of this never-before-seen behavior. Further monitoring may better explain what’s happening, he says. So Las Cumbres, with a global network of telescopes, keeps watch.
Nothing lasts forever, the scientists say—not even this super supernova. “This star will go out at some point,” Arcavi says. “Energy has to run out eventually.”
While the scientists watch and wonder, the eternal God who created the majesties of the universe knows how long each celestial body will live. Psalm 19 tells us that the sky “day to day pours forth speech” to God’s glory. Psalm 148 commands, “Praise Him, Sun and Moon! Praise Him, all you stars!” Even to their dying day.
