By Dean Murray
For the first time, researchers have gotten an incredible first glimpse of a supernova that’s in the process of exploding.
Through detailed observations with the Very Large Telescope (VLT) of the European Southern Observatory, they witnessed the explosive demise of a star right as its outer layers exploded.
This newfound perspective shines a light on the actual shape of supernovae, showing that they take on an olive-like form, rather than being perfectly spherical.
According to the latest update from ESO, “For the first time, astronomers visualized the explosion’s shape during its earliest and most transitory moment. This quick initial phase would have been missed a day later, providing answers to numerous questions about how massive stars go supernova.”
When the supernova named SN 2024ggi was first spotted on the night of April 10, 2024, local time, lead researcher Yi Yang, an assistant professor at Tsinghua University in China, coincidentally landed in San Francisco after a lengthy flight.
Realizing the need for prompt action, he quickly submitted a request for observation to ESO. Remarkably, within 12 hours the request was approved, leading to the VLT turning its powerful lenses toward the supernova on April 11, just 26 hours after it was initially detected.
SN 2024ggi resides in the galaxy NGC 3621, situated in the direction of the Hydra constellation, and at a distance of simply 22 million light-years away—quite close on a cosmic scale. Equipped with a massive telescope and the appropriate instruments, the team recognized this unique opportunity to study the explosion’s characteristics right after it unfolded.
The origin of the supernova was a red supergiant star, which possessed a mass between 12 to 15 times that of our Sun and a radius 500 times larger. Hence, SN 2024ggi stands as a classic representation of a massive-star explosion.
Dietrich Baade, an astronomer at ESO and co-author of the research published in Science Advances, mentioned that “the initial observations from VLT captured a phase during which matter that was accelerated by the explosion burst through the star’s surface. We managed to observe the structure of the star and its explosive event coexist for several hours.”
Yang elaborates, “Understanding the geometry of a supernova explosion is crucial; it reveals fundamental details about how stars evolve and the physical processes that give rise to these cosmic spectacles.”
According to ESO, scientists continue to debate the precise mechanisms that drive supernova explosions in massive stars—specifically those with masses over eight times that of the Sun.
ESO stated, “With this critical knowledge, astronomers are discarding some existing supernova models and enriching others with new data, paving the way for further understanding of how massive stars meet their dramatic end. “
Ferdinando Patat, another astronomer from ESO and co-author, remarked: “This groundbreaking find not only alters our perspective on how stellar explosions occur but also exemplifies what can happen when scientists collaborate across borders. It’s a strong reminder that curiosity and teamwork can open new doors to insights concerning the physics that governs our cosmos. “
