Roughly 13.7 billion years ago, in the rush of the Big Bang, the universe began.
For millions of years the universe was too hot to handle anything more complex than solitary particles, but, 13.3 billion years ago, space had cooled down enough for the first stars to form.
Shortly after that, the star SM0313 was born.
The star, says io9, is the oldest ever discovered, a relic of the ancient universe. SM0313 resides just 6,000 light years away, says Reuters. Despite its ancient age, say the researchers in their study, SM0313 wasn't the product of the first wave of star formation. It likely came in the second wave.
SM0313 is competing with another star, HD 140283, for the title of oldest-known star. HD 140283 was crowned as the oldest ever discovered by researchers early last year.
These sorts of age determinations come with a lot of uncertainty, though, making crowning a true “oldest star” difficult. For example, HD 140283 was calculated to be somewhere between 13.2 to 14.6 billion years old. But, we're pretty sure that the universe is only 13.7 billion years old, putting HD 140283 squarely in the range of the beginning of star formation.
“Truthfully,” said Anna Frebel, one of the researchers on the project to Sci-News.com, “we don’t actually know how old SM0313 is. This is because, sadly, we can’t determine a specific age of these kinds of objects. However, the chemical composition of SM0313 tells us that it is a second-generation star in the Universe which naturally makes this star nearly as old as the Universe itself.”
There have been older stars than even these two, scientists know that much. But the earliest stars also had relatively short lives, burning big and bright and blowing themselves out in just a few million years.