The research from the European Space Agency (ESA) and NASA found there was no evidence of a type of star known as Population III stars, as far back as when the Universe was just 500 million years old. By using the Hubble Telescope, scientists are able to peer back as early as 500 million years after the Big Bang.
In their analysis, the researchers found no evidence of these Population III stars 500 million years after the Big Bang – when the cosmos first burst into life – suggesting they had already been and gone.
Population III stars, which are still hypothetical, were created with the materials left over from the Big Bang – hydrogen, helium and lithium, the only elements that existed at the time.
Population III stars are theorised to be up to 300 times the mass of the Sun, and free of all metals.
Population I stars, such as our Sun, are those found in the disk and spiral arms of a galaxy like the Milky Way.
Population II are found in the galactic bulge, the halo that surrounds our galaxy.
Theoretically, Population III stars would have formed earlier than its predecessors, but is given the three tag because the other two were established first.
However, by looking back in time to a period dating 500 million to one billion years after the Big Bang, experts only discovered Population I and II stars.
What this suggests is that ‘modern’ stars, emerged much earlier in the Universe than previously thought as the materials to create them would have been in the Universe.
Rachana Bhatawdekar of ESA and the lead author of the study said: “We found no evidence of these first-generation Population III stars in this cosmic time interval.
“These results have profound astrophysical consequences as they show that galaxies must have formed much earlier than we thought.
“This also strongly supports the idea that low-mass/faint galaxies in the early universe are responsible for reionization.”
The Hubble Space Telescope will be retired in the coming year, with the James Webb Space Telescope (JWST) taking its place in 2021.
The JWST is so powerful it will reach back to the furthest realms and the earliest moments of the universe.
JWST, which is named after NASA’s second administrator James Webb who served from 1961 to 1968 and played a major part in the Apollo missions, has the capability of scanning thousands of planets for alien life – even though those planets are thousands of light-years away.
One of the major differences between Hubble and JWST will be how far back in time it will be able to see.
Hubble can see far into space and is essentially looking back in time as light travels to the craft.
Through Hubble, experts have been able to view the formation of the first galaxies, about one billion years after the Big Bang.
However, as JWST is much more powerful, it will be able to see just 0.3 billion years after the Big Bang to when visible light itself was beginning to form.