Recent data harvested from the James Webb Space Telescope (JWST) strongly suggests that millions of supermassive stars, potentially up to 10,000 times the mass of the sun, formed during the early stages of the universe, are hiding among the clusters of stars.
These colossal stars, referred to as "celestial monsters" by researchers, emerged a mere 440 million years after the Big Bang.
This discovery can potentially provide valuable insights into the origins of heavy elements in our universe.
The findings were published on May 5 in the journal Astronomy and Astrophysics.
"Today, thanks to the data collected by the James Webb Space Telescope, we believe we have found a first clue of the presence of these extraordinary stars," lead study author Corinne Charbonnel, an astronomy professor at the University of Geneva in Switzerland, said in a statement.
By examining globular clusters — clumps of tens of thousands to millions of densely packed stars and some of the oldest formations in the universe — researchers have discovered chemical traces of gigantic stars. These globular clusters, which are around 180 in number in our Milky Way galaxy, provide astronomers with a glimpse into the early years of the universe.
Interestingly, certain stars within these clusters exhibit significant variations in their elemental composition, specifically in oxygen, nitrogen, sodium, and aluminium, despite originating from the same gas and dust clouds approximately 13.4 billion years ago.
Astronomers propose that this diversity in elemental proportions may be attributed to the presence of supermassive stars. These cosmic heavyweights, born in the denser conditions of the early universe, burned their fuel at exceptionally high temperatures, resulting in the production of heavier elements that subsequently "contaminated" smaller, younger stars primarily composed of lighter elements.
However, locating these supermassive stars has proved challenging. These fiery giants, estimated to be 5,000 to 10,000 times the mass of our sun, existed at temperatures as high as 135 million degrees Fahrenheit (75 million degrees Celsius).
Due to their colossal size, brightness, and extreme heat, these cosmic monsters met their demise in violent explosions known as hypernovas, as more massive, luminous, and hotter stars have shorter lifespans.
"Globular clusters are between 10 and 13 billion years old, whereas the maximum lifespan of superstars is two million years. They therefore disappeared very early from the clusters that are currently observable. Only indirect traces remain," co-author Mark Gieles, a professor of astrophysics at the University of Barcelona, said in the statement.