Shakti and Shiva: Ancient Star Duos in Milky Way Galaxy's Tale of Creation

Scientists have recently uncovered two ancient streams of stars within the Milky Way Galaxy, dubbed Shakti and Shiva, shedding light on the galaxy's earliest formation stages. These star structures, identified using data from the Gaia space telescope, are believed to have merged with the Milky Way around 12 billion years ago, providing vital clues about its early evolution.

Named after Hindu deities, Shakti and Shiva consist of stars with similar chemical compositions, suggesting they formed roughly 12-13 billion years ago. Each structure boasts a mass about 10 million times greater than the sun, underscoring their significance in the galaxy's formative years.

This discovery marks a crucial milestone in understanding the galaxy's turbulent infancy.

Lead researcher Khyati Malhan from the Max Planck Institute for Astronomy highlights the study's importance in addressing fundamental questions about galaxy formation. The Milky Way, a vast spiral galaxy hosting billions of stars, has its origins traced back to these primordial star structures.

Gaia, launched in 2013, played a pivotal role in identifying Shakti and Shiva, leveraging its precise mapping capabilities to detect their presence. Situated within 30,000 light years of the galactic center, these star streams provide valuable insights into the Milky Way's earliest stages.

The study builds upon previous findings, including the identification of the "poor old heart" of the Milky Way, another population of ancient stars within the galactic core. Shiva and Shakti's distinct composition, characterized by lower metallicity, sets them apart from other stars in the galaxy.

As researchers delve deeper into the Milky Way's history, future Gaia surveys hold promise in unraveling its evolution from its inception over 13 billion years ago. Malhan emphasizes the need for comprehensive studies to paint a clearer picture of the galaxy's formation and evolution over its vast cosmic timeline.