Watch: Dying star turns into supernova 22M light-years away
What's the story
In a groundbreaking discovery, scientists at the European Southern Observatory (ESO) have captured the first moments of a dying star. The event was witnessed using the Very Large Telescope (VLT) in Chile, which observed supernova SN 2024ggi in April 2024. The research team was able to see this cosmic phenomenon at its earliest and most fleeting stage for the first time ever. The findings were published in Science Advances.
Cosmic fireworks
Supernova's shape and its significance
The initial explosion of the supernova was found to have an olive shape. As the material expanded and collided with surrounding matter, it flattened while keeping the same axis of symmetry. This observation wasn't a colorful explosion but a reconstruction of its geometry from light polarization. Yi Yang, an astronomer from Tsinghua University and co-author of the study, emphasized that "the geometry of a supernova explosion provides fundamental information on stellar evolution."
Stellar evolution
Understanding supernovae: A cosmic phenomenon
Supernovae occur when a massive star, much larger than our Sun, exhausts its fuel and dies. The core collapses and the outer mass falls inward before bouncing outward. This process releases a tremendous amount of energy, making the supernova incredibly bright. The "bounce shock" has been a mystery for decades, Yang wrote in the study. Supernova SN 2024ggi is located in galaxy NGC 3621, some 22 million light-years away from us.
Observational breakthrough
Spectropolarimetry: A key technique in supernova observation
The ESO scientists used a method called spectropolarimetry to capture the fleeting "breakout" shape of the supernova. Lifan Wang, an astronomer at Texas A&M University and co-author of the study, noted that this technique provides information about the explosion's geometry that other observational methods cannot. This innovative approach has given researchers unprecedented insight into these cosmic fireworks and their underlying processes.