Scientists from the University of Cambridge and the Australian National University have discovered numerous ancient stars in the center of our galaxy. These scientists believe that the stars represent some of the oldest stars in our galaxy, and quite possibly the universe as a whole.
Such ancient discoveries are important because they allow astronomers to peer into the past, seeing what the universe was once like, and how it evolved into what we know today.
For centuries now researchers have been peering into the sky, trying to unlock the universe’s mysteries. This time around scientists were searching for stars low in metals. Wondering why that’s so significant?
Most scientists believe that when the universe came into creation some 13.7 billion years ago, it consisted only of hydrogen, helium, and trace amounts of lithium.
Metals and all the other elements we know were formed through the fusion processes that power stars. As atoms were smashed together by immense amounts of gravity, they fused, creating heavier and heavier atoms, like iron.
Scientists believe that many of the oldest stars would be all but devoid of metal and should be located somewhere in the middle of the galaxy.
To hone in on the stars, researchers used telescopes in both Australia and Chile and selected a pool of about 14,000 candidate stars. Then, they used spectrography to hone in on 23 stars with low metal content.
Next, the researchers looked at the remaining stars and their trajectory more closely. They found that seven of these stars were sitting right in the middle of the galaxy, far from other stars, and were most likely born at the beginning of the universe.
These ancient stars probably weren’t the first stars ever born. Most of those stars are likely dead. As far as still burning stars, however, they may well be the oldest still shining.
The stars are detailed in a new paper, published this week in the journal Nature.