In a new find, astronomers at Las Cumbers Observatory have discovered a star that has exploded multiple times over a period of more than fifty years has not died yet. That means supernova has not lead to the death of the star. This surprising observation has pushed the astronomers to rethink about how stars die and have challenged the existing theories on these cosmic catastrophes.
Supernova is an event in which the star explodes and dies. That means Supernova occurs during the last stage of a massive star’s life leading to catastrophic explosion of star. Astronomers have seen thousands of supernovas resulting in the death of the star. However, this supernova has defied expectations and has been lasting far longer than anticipated. The supernova, named as iPTF14hls, was first seen in September 2014 by the Intermediate Palomar Transient Factory telescope situated near San Diego. At first, the scientists thought it to be an ordinary supernova. But later they found out that the supernova was glowing brighter again after it had faded. So, they eventually classified the bright object as a type II-P supernova. This supernova is situated about 500 million light-years away from Earth in the constellation Ursa Major.
Actually, supernovas are one of the most powerful explosions in the Universe, emitting out the brightness of around 100 million suns. But their brightness lasts for only about 100 days, and after that they become dim. But the Supernova iPTF14hls was completely different from others. It grew brighter and dimmer at least five times over three years. UC Santa Barbara undergraduate student Zheng Chuen Wong while studying old data found out that the Super Nova was growing brighter even after surviving 135 to 140 days.
Lead author Lair Arcavi, an astrophysicist with UC Santa Barbara and Las Cumbres, a Goleta, Calif.-based global observatory network said that he was shocked after getting the data from Wong. He said that at first he did not believe it to be a Supernova but after studying the spectrum, he was assured that it was a common type of supernova with some extraordinary features. The supernova ultimately stayed bright for more than 600 days and still looked quite young. The study calculated that the star that exploded was at least 50 times more massive than the sun and probably much larger. Dr. Arcavi said that this supernova broke everything that they thought before about how they work. And it is the biggest puzzle that he has encountered in almost a decade of studying stellar explosions.