Feb. 21 (UPI) — An amateur astronomer has captured the fleeting first light of an exploding star. It’s the first time anyone has documented the “first optical light” of a supernova.
Stars explode all the time, but they do so at random, making it extremely difficult to document the sudden burst of light that proceeds their explosion.
Victor Buso, an amateur astronomer from Rosario, Argentina, was just testing out his new camera and telescope in Sept. 2016, when he lucked his way into before-and-after images of an exploding star inside NGC 613, a spiral galaxy located 67 million light-years from Earth.
While analyzing the images captured by his new camera, Buso noticed a unique flash of light. He got in touch with professional astronomers and shared his discovery with them. The researchers mobilized telescopes around the globe to follow up on Buso’s observations.
“Professional astronomers have long been searching for such an event,” Alex Filippenko, an astronomer at the University of California, Berkeley, said in a news release. “Observations of stars in the first moments they begin exploding provide information that cannot be directly obtained in any other way.”
The explosion of a massive star begins with a “shock breakout.” As a wave of supersonic pressure ripples outward form the core, the surface of the star is heated to extreme temperatures, causing the star to brighten suddenly. Buso’s camera captured this intense burst of light.
Scientists dubbed the flash and subsequent supernova explosion SN 2016gkg. In the months following Buso’s discovery, astronomers all over the world watched the exploded star, learning more about its classification and the nature of its dramatic death.
Researchers estimated Buso’s chance of happening upon the first light of a supernova at between one and 10 million and one in 100 million.
“It’s like winning the cosmic lottery,” said Filippenko.
Spectral analysis of the exploded star proved Buso had witnessed the first light from a Type IIb supernova, the explosion of a massive star that had already lost the majority of its hydrogen shell.
When scientists combined their observations with a model of stellar evolution, they determined the star was originally 20 times the mass of the sun. However, the simulations showed the star likely lost 75 percent of its mass to a companion star prior to its explosion.
Researchers shared their analysis in a new paper published this week in the journal Nature.