The discovery of a very bright supernova (PS1-10-afx) left the scientific community speechless last year. Now, a team of researchers from the University of Tokyo (Japan) has explained that what gave this supernova so much luminosity was the presence of a nearby galaxy that acted as a “magnifying glass” or gravitational lens .
The resolution of this mystery, which has been published in the journal Science , seems to end the controversy of the most luminous stellar explosion of its kind, since it came to shine 30 times more than expected . At first there were two hypotheses that gained strength: first, that it was a new type of super-bright supernova ever seen; second, that there was something that acted as a magnifying glass giving it an extra luminosity, a hypothesis that has proven to be the true one.
“We thought that the supernova’s exceptional brightness was generated by an associated lens, but we had no direct evidence of its presence , so the explanation seemed like it required a bit of magic,” says Robert Quimby, lead author of the study.
The researchers suspected that this intermediate object would have to remain there even if the supernova had already vanished, so to confirm its existence they used spectroscopic data provided by the Keck-I telescope in Hawaii (USA) to analyze the galaxies near the supernova. No sooner said than done. The data revealed two sets of gas emission lines in the spectrum, leading the experts to deduce that there was a galaxy right in front of it, at an ideal distance to amplify the light from the supernova that caused such a stir.
