This supernova is the most luminous and energetic ever observed!

Even though Betelgeuse's recent variations kept us going, animated by the hope of observing the red supergiant turn into supernova, scientists were studying an even more spectacular cosmic event. Discovered by the telescope Pan-STARRS in Hawaii, in 2016, the supernova SN2016aps has just been the subject of a four-year study, during which it was observed from every angle by the team of Harvard-Smithsonian Center for Astrophysics (CfA). Here is what they discovered.

A supernova like no other

" SN2016aps is remarkable in many aspects ", Edo Berger comments, professor at Harvard University and co-author of the study, published in the review Nature Astronomy. " Not only is it the brightest supernova ever, but it also has several properties and characteristics that make it a rare item compared to other explosions ofstars in L'universe. "
Indeed, by studying the spectacular release ofenergy from SN2016aps, the team was able to reveal that the latter was reaching unprecedented proportions: 10⁵² erg, against 10⁵¹ erg for a typical supernova. Furthermore, while in a conventional situation only 1% of the energy of the explosion is converted into light visible, in the case of SN2016aps, the measured radiation corresponds to half of the total energy. Result: our supernova is 500 times brighter than its counterparts.

Giantess girl

The astonishing release of energy from SN2016aps leads researchers to think that the star that preceded it would have been incredibly massive, " at least 100 times the mass of our Sun Adds Berger. In the last moments before his death, the star – called "progenitor" – would have lost an immense layer of gas. The interaction between the latter and the debris from the collision would directly contribute to the brightness atypical of SN2016aps.

Another surprise: the researchers detected an unusual amount ofhydrogen in the cosmic architecture of the supernova. This characteristic could suggest that instead of a star unique, SN2016aps is said to come from two slightly less massive stars that have merged. In fact, the hydrogen in massive stars generally dissipates well before they enter the pulsation phase, which signals their ultimate jolt. Smaller stars, on the other hand, retain enough of their gas to justify the rates observed at SN2016aps.

" The identification of SN2016aps has opened new avenues in the identification of similar events in the first generations of stars ”, enthuses Berger. "With the advent of LSST, we can find such explosions at the heart of the first billion years of the universe. "