Astronomers have discovered a small galaxy located on the edge of the Milky Way Galaxy that might be the first galaxy formed in the universe.
The galaxy was called Segue 1 in an article in Scientific American reports, according to Fox News.
The researchers believe Segue 1 could be a fossil left over from the beginning of the universe after a recent study discovered that it features less heavy elements such as metal. Metal is common in all known galaxies.
The measurements of Segue 1 were reported in a paper accepted for the Astrophysical Journal, The Daily Galaxy reported. The stars were almost entirely made of hydrogen and helium and contain small amounts of heavier elements like iron. No other galaxy holds as little heavy elements as Segue 1, which makes the galaxy the "least chemically evolved galaxy known." This means the galaxy may have stopped evolving about 13 billion years ago.
"Segue 1 is so ridiculously metal-poor that we suspect at least a couple of the stars are direct descendants of the first stars ever to blow up in the universe," said Evan Kirby, study co-author from the University of California, Irvine. "Segue 1 is the only example that we know of now that was never enriched by these low-mass stars, meaning it formed stars really quickly, in the blink of an eye. If it had formed stars long enough those low-mass stars would have to contribute."
The size of Segue 1 shows that the galaxy may have gone through rapid growth before stopping, Fox News reported. Astronomers are debating on how the sudden stop in growth could have taken place.
Some astronomers believe the galaxy use to be larger but the Milky Way took away some of its stars that were rich in metal. Others believe the galaxy was actually created at its small size. The idea of Segue 1 starting out small has not been thought possible before, and it suggests the existence of more galaxies similar to Segue 1.
