Twice-dead star explodes 50 years later

Nov. 8 (UPI) -- It's the star that keeps on dying -- astronomers have discovered a star that's exploded several times over the last half-century.

Scientists first noted supernova iPTF14hls in September 2014. The fresh explosion seemed like the average type II-P supernova. The glow of such explosions usually last for 100 days. This supernova remained bright for 600 days.

When researchers examined archival observations of this specific spot in the sky, they found a 1954 explosion in the very same location.

Apparently, the star suffered a fiery near-death explosion, survived, and then exploded again five decades later.

"This supernova breaks everything we thought we knew about how they work," Iair Arcavi, an astronomer at the University of California Santa Barbara and Las Cumbres Observatory, said in a news release.

The supernova was first spotted using an instrument designed by Nick Konidaris, an astronomer at the Carnegie Institution for Science. The SED Machine is designed to analyze astronomical data and identify and classify transient events.

According to the SED Machine, iPTF14hls brightened and dimmed some five times over three years.

"I never expected it would help us analyze an explosion as strange as this zombie star," Konidaris said of his invention.

Researchers described the zombie star in a paper published this week in the journal Nature.