Death of a star: Scientists get front-row seat to witness a supernova

A star explodes almost every second or so somewhere in the universe, and scientists got a front-row seat to witness one for the first time in the history of astronomy. The observation offered an unprecedented glimpse to the scientific community into how stars go supernova.

The team, led by scientists from Northwestern University and the University of California, Berkeley, saw the violent show of the red supergiant self-destructing and collapsing into a Type-II supernova using specialized imaging equipment at the W.M. Keck Observatory in Hawai’i. A Type-II supernova results from the rapid collapse and explosion of a massive star.

Located in the NGC 5731 galaxy, approximately 120 million light-years from Earth, the particular star was 10 times bigger than the sun when it exploded. The team observed the star during its final 130 days. The new discovery provides fresh insight into the death of a star — it was previously thought that red supergiants were dormant before their deaths with no evidence of luminous emissions or violent eruptions.

In their study published in The Astrophysical Journal, the researchers said the behaviour of massive stars in their final evolutionary years was almost unconstrained. However, the new observations detected bright radiation from a red supergiant in its final year before exploding, suggesting that at least some of these stars must undergo significant internal structural change.

Supernova is the explosion of a star that leads to debris and particles being shot into space. A supernova burns only briefly, but it can offer scientists an idea about how the universe began. One type of supernova has suggested that the universe is expanding at an ever-increasing rate. Scientists have also determined that supernovae play a key part in distributing elements throughout the universe.

“Without supernovae, life would not be possible,” said NASA.

“Our blood has iron in the haemoglobin which is vital to our ability to breathe. We need oxygen in our atmosphere to breathe. Nitrogen enriches our planet’s soil. Earth itself would be a very different place without the elements created in stars and supernova explosions.”

Red stars are the largest stars in the universe in volume terms.

In 2019, scientists found the red supergiant Betelgeuse, located in the Milky Way, dimming to its lowest level of brightness in years. This prompted some astronomers to believe it might be about to go supernova. However, the Betelgeuse remains intact, unlike the star in NGC 5731.