The death of a star is always a remarkable cosmic event, and scientists have been fortunate enough to witness the funeral panorama taking place in the distance.
Ground-based telescopes provide a detailed look into the dying period of a supergiant star for the first time. Although not the brightest stars or large bodies, the volume of recently deceased stars is still among the largest.
One of the most widely known supergiant objects is Betelgeuse, famous for its time-lapsed flashes. Science has long predicted the death of a massive star, but it still exists to illuminate a swath of space.
The star mentioned in the new report is located in the galaxy NGC 5731. It is 120 million light-years away, and 10 times the size of the Sun before the supernova exploded. According to what science is known, supergiant stars 40 times more massive than the Sun will not be able to turn into red supergiant stars.
The last breath of the star is released violently, forming a dense layer of hot gas. Before the special event was observed, scientists believed that red supergiant stars often passed away in silence before exploding supernovas, or collapsing into dense neutron stars.
Instead, the massive star self-destructs in a surprising way before collapsing to create a Class II supernova (Type I explosions are brighter, possess a spectrum that does not contain traces of hydrogen, and spread through space about twice as fast as a classical type I explosion).
After burning away all the hydrogen, helium and other elements that exist, the star will be left with only an iron core. Running out of fuel and unable to fuse with iron, the star’s core collapses and explodes. Event details are described in a new report published in The Astrophysical Journal.
“This is a new breakthrough in understanding the state of supergiant stars before death,” said lead author of the report, researcher Wynn Jacobson-Galán. According to him, science has never known the activity of a supergiant red star before a type II explosion.
“For the first time, we see a supergiant red star explode‘, says Jacobson-Galán.
Astronomers caught the news early 130 days before the event. In the summer of 2020, a telescope located at the University of Hawaii’s Pan-STARRS Astronomy Institute detected bright radiation. In the fall of that same year, scientists witnessed a supernova explosion at the very spot where the radiation was emitted. The explosion was assigned the name “SN 2020tlf”.
Observations revealed a host of matter suspended around the star, hot plumes of gas continuously emanating from the star throughout the summer of 2020.
“It’s like we’re watching a ticking time bomb‘, said senior researcher Raffaella Margutti. “So far, we have never confirmed such intense activity coming from a supergiant red star, and then seeing it emitting such bright gas.“.
New research shows that such stars undergo a series of internal changes that cause gas to escape so strongly as the star slowly dies.
“I’m excited by all the ‘unknowns’ that come up after this discovery” said Mr. Jacobson-Galán. “Detecting more events like SN 2020tlf will have a major impact on how we define the last moments of a star’s life, uniting observers and hypotheticals with a single goal, Solve the mystery surrounding the end of life“.
According to CNN