Astronomers peering into the heart of the Milky Way have discovered two gargantuan, never-before-seen structures. These vast"streams" of stars each contain the mass of 10 million suns and are up to 13 billion years old. They span wide swathes of the galaxy and may be some of the earliest building blocks of our Milky Way, scientists with the Max Planck Institute for Astronomy said.
Related: James Webb telescope confirms there is something seriously wrong with our understanding of the universe The millions of stars that make up Shiva and Shakti also seem to have contributed to our galaxy's overall structure but are located a bit further from the galactic center than previously identified fragments like the Gaia sausage.
The team's analysis showed that Shakti's stars orbit further from the galactic center and in a more circular orbit than Shiva's — but both structures contain stars that are extremely metal poor, meaning they lack the heavier elements forged through stellar fusion later in the universe's history. This means Shiva and Shakti likely contain some of the oldest stars in the Milky Way, making the newfound streams some of the first building blocks upon which the galaxy evolved.