When astronomers discovered the SN2016aps supernova in 2016, they knew they were dealing with something colossal, though not exactly what its magnitude was.
Today they already have more certainties.
it is the “brightest, most energetic and probably most massive supernova ever identified”.
Scientists at the Harvard & Smithsonian Center for Astrophysics came to that conclusion after four years of studying the supernova located in a galaxy 4 billion light-years away.
A supernova is a powerful, luminous explosion from a dying star. In the process it releases an enormous amount of energy.
The SN2016aps explosion is one of the most energetic cosmic phenomena ever captured from Earth.
“At its peak, this supernova was 110 billion times the mass of our Sun, ” astrophysicist Edo Berger, one of the co-authors of the study published in Nature Astronomy.
“Equivalently, the total energy of the supernova explosion was ten times greater than the Sun’s total energy output over its entire 10-billion-year lifespan,” he adds.
Scientists theorize that the SN2016aps explosion is the result of the merger of two massive stars. Exploding stars generating a phenomenon called “pulsating pair instability” .
What was discovered?
Researchers from the Harvard & Smithsonian Center for Astrophysics. And the universities of Birmingham, Northwestern Ohio identified the supernova for the first time in 2016. Using data from the Panoramic Sounding Telescope and Rapid Response System (Pan-STARRS).
Over the next four years they tracked their slow evolution and release of energy.
Matt Nicholl of the University of Birmingham and lead author of the study, explains that the study revealed a disturbing story of the parent star.
“We determined that in the last few years before it exploded, the star threw out a huge shell of gas as it throbbed violently. The collision of the debris from the explosion with this huge shell led to the incredible brilliance of the supernova. Essentially it added fuel to the fire.”
That is why the SN2016aps supernova radiated 50% more energy than a typical supernova. Something that is considered “unprecedented” in the study of these phenomena.
The high level of hydrogen gas in this cosmic event was also surprising.
Massive stars generally lose most of their hydrogen to stellar winds. Such as those that reach Earth from the Sun long before approaching their burst event.
“That SN2016aps clung to its hydrogen led us to theorize that two less massive stars had fused together. Since lower-mass stars retain their hydrogen longer,” Berger explains.
The new star, born from the fusion. Charged with hydrogen and was also high enough in mass to cause instability.”
N2016aps: What does this finding imply?
First, the very fact of discovering and analyzing it is enriching, as these types of supernova explosions are incredibly rare.
It is not trivial to remove such a needle in a haystack in real time. And that it can be studied in great detail.
Another point to note is that this is the first time that a supernova has offered evidence to support the pulsating pair instability theory.
“This is the first supernova we’ve seen that fits this theoretical idea,” says the astrophysicist.
And third, this finding will also allow science to understand how the first generations of stars originated.
“With the Great Synoptic Tracking Telescope (LSST) we can find such explosions that occurred in the first 1 billion years in the history of the universe,” says Berger.