Some of the universe’s oldest stars have been discovered in the Milky Way
Some stars in our very own Milky Way are some of the earliest ever seen, according to research published today in the Monthly Notices of the Royal Astronomical Society.
The stars are in the Milky Way’s halo, a shroud of stars that surrounds the galactic disk. The stars are also relatively close, at just 30,000 light-years from Earth. The team found that the stars are between 12 billion and 13 billion years old, clocking them to around the same time as the earliest stars we can see. The first stars in the whole universe didn’t show up until the universe was about 100 million years old, meaning the recently spotted stars were very early additions to the universe’s stellar content.
The stars were found in data collected by the Las Campanas Observatory’s Magellan-Clay telescope. They appeared metal-poor—specifically lacking in strontium and barium—akin to the stars previously found in ultra-faint dwarf galaxies, some of the most ancient galaxies which also may be the building blocks of the Milky Way. [Continue reading…]