GARCHING, Germany, June 17 (UPI) -- Astronomers in Europe have gathered what they say is the best evidence yet of the universe's first generation of stars.
The universe is nearly 14 billion years old. But by looking deep into space, at light that's been traveling for billions of years to reach the lenses of our telescopes, scientists can peer back in time and see cosmic structures as they were not longer after the birth of the universe.
Recently, the European Southern Observatory's (ESO) Very Large Telescope (VLT) spotted the brightest galaxy ever located in the early universe. Astronomers believe the first generation of stars are lurking inside the young, hot galaxy, dubbed CR7.
The VLT's instruments found that CR7 featured strong ionised helium emissions, but no signs of heavier elements.
This confirmed astronomers suspicion that CR7 may host the universe's first crop of stars, what scientists call Population III stars.
These original stars forged the heavier elements -- oxygen, nitrogen, carbon and iron -- that helped birth future stars and eventually made life possible. But Population III stars themselves were born of material present prior to the dawn of stars -- hydrogen, helium and trace amounts of lithium.
The discovery of CR7 and several other young, bright galaxies was exciting on its own. But the subsequent surprise is a game changer. Both were detailed in a new study published in the Astrophysical Journal.
"The discovery challenged our expectations from the start, as we didn't expect to find such a bright galaxy," explained lead researcher David Sobral, a professor and astronomer with the University of Lisbon in Portugal and Leiden Observatory in the Netherlands.
"Then, by unveiling the nature of CR7 piece by piece, we understood that not only had we found by far the most luminous distant galaxy, but also started to realise that it had every single characteristic expected of Population III stars," Sobral said. "Those stars were the ones that formed the first heavy atoms that ultimately allowed us to be here. It doesn't really get any more exciting than this."
Followup observations by VLT, ALMA, and the Hubble Space Telescope will look to confirm the presence of Population III stars.
"I have always wondered where we come from. Even as a child I wanted to know where the elements come from: the calcium in my bones, the carbon in my muscles, the iron in my blood," said study co-author Jorryt Matthee.
"I found out that these were first formed at the very beginning of the Universe, by the first generation of stars. With this discovery, remarkably, we are starting to actually see such objects for the first time."