Scientists have discovered a supernova that exploded in a distant galaxy within the first billion years after the Big Bang. It is classified as a Type II supernova, meaning it was caused by the collapse of a giant star. It has been named after Eos, the goddess of dawn.
Supernovae and the evolution of stars
Supernovae (SN) are powerful and bright stellar explosions. They are important to the scientific community because they provide key clues about the evolution of stars and galaxies. In general, supernovae are divided into two groups based on their atomic spectra: Type I (no hydrogen in the spectrum) and Type II (with hydrogen spectral lines).
These phenomena occur as a result of the rapid collapse and explosion of massive stars (with a mass greater than 8 solar masses). Type II supernovae with core collapse (CC SN), which can be brighter than the total radiation of their host galaxies, allow astronomers to study the final stages of stellar evolution, and studies of Type II CC supernovae in the early Universe may be important for constraining models of early stellar evolution.
Goddess of Dawn
Now, a group of astronomers led by David A. Coulter of Johns Hopkins University in Baltimore, Maryland, may have discovered such a Type II supernova in the early Universe. They report that, using a method called gravitational lensing, which causes multiple magnified images of a background object to appear, they were able to identify a supernova that would have been too faint to detect by other methods.
The supernova was named Eos after Titan, the goddess of dawn in Greek mythology. It has a spectroscopic redshift of 5.133 and is located in a very faint galaxy emitting the Lyman-alpha line. This makes it the most distant spectroscopically confirmed supernova ever discovered.
Characteristics of supernova SN Eos
The collected data indicate that SN Eos exploded when the Universe was only about 1 billion years old, shortly after it had been reionized and became transparent to ultraviolet radiation. Measurements taken by Coulter’s team indicate that SN Eos exploded in an environment with a metal concentration less than 10% of that of the Sun.
The study showed that SN Eos had variable, bright, and increasing radiation in the far ultraviolet (FUV) range in its own reference frame. Analysis of the ultraviolet radiation indicates that SN Eos is a Type IIP supernova in the final stage of its plateau phase. In general, Type II-Plateau supernovae (SNe IIP) remain bright (on a plateau) for a long time after reaching their maximum.
The authors conclude that SN Eos is an example of a strongly gravitationally lensed, multiply imaged, extremely metal-poor Type IIP supernova. They note that the discovery of this supernova highlights the main goals of the JWST mission: understanding the life and death of the first stars, the origin of elements, and the formation and evolution of the youngest galaxies.
According to phys.org
