Segue 1 dwarf galaxy hints at universe's first stars

The Segue 1, referred to as the "least chemically evolved galaxy known," could hint at the universe's very first stars, according to researchers who recently studied the tiny galaxy. Among all known galaxies, Segue 1 has significantly fewer stars and less heavy elements, revealing an estimated end to its evolution 13 billion years ago.

The information was revealed in the Astrophysical Journal, where MIT's Anna Frebel and fellow researchers detailed their findings regarding the small galaxy's composition. Heavy elements like iron are found only in trace amounts, leaving most of the composition as helium and hydrogen.

Said Evan Kirby, the study's co-author, "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." He went on to explain that stars formed very quickly in Segue 1, and ultimately poses a question about why star formation stopped.

Further research could then reveal reasons why a galaxy may have stopped evolving, as well as lending an insight into galaxy formation and the very earliest parts of the universe's formation. It is said other tiny galaxies like Segue 1 could abound, remaining yet undiscovered.

SOURCE: Nature