Discovering the First Stars' Explosions: Unveiling the Universe's Origins with ESO's VLT

For the first time, researchers have uncovered evidence of the first stars' explosive deaths using the European Southern Observatory's (ESO) Very Large Telescope (VLT). They identified the chemical fingerprints of three distant gas clouds, whose composition aligns with expectations from the Universe's initial stellar explosions. This discovery brings us closer to comprehending the nature of the first stars formed after the Big Bang.

It is believed that the Universe's first stars, which emerged 13.5 billion years ago, were vastly different from present-day stars. Comprised of only hydrogen and helium, these massive stars quickly perished in powerful supernovae, enriching surrounding gas with heavier elements. Subsequent generations of stars were born from this enriched gas, further dispersing heavier elements upon their deaths. To learn more about these long-vanished stars, scientists like Stefania Salvadori, Associate Professor at the University of Florence, study the chemical elements they dispersed after their demise.

Utilizing ESO's VLT in Chile, researchers discovered three extremely distant gas clouds with chemical fingerprints consistent with the first stars' explosions. Depending on the mass and energy of these early stars, the initial supernovae released varying chemical elements, such as carbon, oxygen, and magnesium. However, some explosions were not powerful enough to expel heavier elements like iron. The team therefore sought distant gas clouds lacking iron but abundant in other elements. They found three such clouds in the early Universe, revealing the explosive remnants of the first stars.

This unique chemical composition has been observed in numerous ancient stars within our galaxy, which scientists consider second-generation stars formed from the first stars' remnants. This study uncovers these remnants in the early Universe, adding a crucial piece to the cosmic puzzle. Salvadori explains that their discovery offers new opportunities to indirectly study the nature of the first stars, complementing

ESO

Research paper