When the Universe was less than one percent of its current age, 100 million years ago, the very first stars may have appeared. Since then, the Space expansion is rapidTheir light has gone out, and we are left to search for clues in cosmic sources nearer home.
You can analyze the light.Researchers from Japan, Australia and the United States discovered that a “distinctive mixture of heavy elements” emerged from the clouds surrounding a distant quasar. This could only have been possible from one source: a massive supernova of a star of the first generation.
All the stars that can be observed are either Population 1 or Population 2. This classification is based on their age. Population I stars have less heavy elements and are younger. Population II stars contain more heavy element, but are older.
The very first stars – described as Population III – are older still, their existence coinciding with cosmic distances that put them well out of sight of even our best technologies. At this time, we cannot imagine what they might look like.
Scientists believe that the earliest stars may have been super bright and hot, with a mass hundreds of times greater than our Sun.
Population III stars would be made up of only the most basic gases if there were no history of strong cosmic events that produced elements heavier than lithium. In those days, hydrogen, helium and a little bit of lithium were the only materials in the Universe. Big Bang. Heavy elements could only emerge when the first stars collapsed in violence.
These first stars were likely to die with pair-instability Supernovae, which is a type of super-supernova that can only be achieved in massive stars. This would be unlike other supernovae and leave no stellar remnants such as a neutron starOr Black holeInstead, he blasts everything outward in an expanding cloud.
That blast might have seeded ancient interstellar space with the heavy elements needed for the formation of rocky worlds like our own — thus enabling life as we know it — so the net effect is positive.
Astronomers in the Earth are now trying to discover more about Population III stars. However, the light from the mega-explosions of ancient mega-explosions has disappeared into the distance leaving only a diffuse cloud with a complex mixture of elements.
The material in the mixture could become new over time. To find signs of such a concentration of star dust, the authors of the new study used near-infrared spectrograph data from one of the most distant-known quasars — a type of active galactic nucleus, or the extremely luminous center of a young galaxy.
The researchers noted that this quasar’s light had been moving through space for 13.1 trillion years before it reached Earth. That means that we’re now seeing the quasar in the same way it did when the Universe was only 700,000,000 years old.
A spectrograph can be described as an instrument that takes in incoming light and divides it into its component wavelengths. Although this can help determine the elements present in distant objects, it is not always straightforward.
The authors note that the brightness of lines in astronomical spectrumtra may depend on other factors than the abundance of an element. This could complicate efforts to identify particular elements.
Yet two of the study’s authors – astronomers Yuzuru Yoshii and Hiroaki Sameshima, both from the University of Tokyo – had already developed a trick to get around this problem.
The team used wavelength intensity to determine the presence of elements to analyse the cloud composition around the quasar.
The clouds had a 10x higher amount of iron than our Sun, making it a surprisingly low ratio for magnesium to iron. This was a hint, researchers claim, that this material may have been from the first-generation explosion of a star.
“It was obvious that this supernova candidate would be a pair instability supernova of a Population III Star, in which the entire star explodes and leaves no remnant.” SaysYuzuru Yashii, an Astronomer at the University of Tokyo, was co-author.
“I was pleased and somewhat surprised to see that a pair instability supernova of an star with a mass approximately 300 times that the Sun gives a ratio magnesium to iron that matches the low value that we calculated for the quasar.”
Yoshi and his coworkers note that there was at least one more possible trace of a Population III Star in 2014. However, this new discovery is their strongest evidence.
If they’re correct about their findings, this research could be a significant step in understanding how matter evolved throughout the history of the Universe. To be sure, however, they say that more observations are needed to confirm similar traits in other celestial objects.
These observations may not be all that are required to come from distant quasars. Even if there are no more Population III stars left in the Universe, the longevity of their supernova remnants means evidence could be hiding almost anywhere – including the local Universe around us.
“We know now what to look for. We have a path.” SaysTimothy Beers, an astronomer from the University of Notre Dame, was co-author.
“If this occurred locally in the very early Universe (which it should), then we would expect evidence to support it.”
The results were published in The Astrophysical Journal.
