Ancient Stars Discovered in Our Galaxy May Be Among the Universe's Earliest

In a groundbreaking discovery, a team of researchers, led by Anna Frebel from MIT, have uncovered a trio of ancient stars that could be among the oldest in the Universe. These stars, named 'SASS' (Small Accreted Stellar System stars), are moving very quickly and in the opposite direction to most other stars in the Milky Way, suggesting they started life outside our galaxy.

The SASS stars are considered part of the cosmic family tree, as they were formed during the early stages of the Universe and produced heavier elements, which were incorporated into subsequent generations of stars. The earliest stars, primarily composed of hydrogen and helium, were created during the Big Bang. These ancient SASS stars have an abundance of heavy elements, indicating they formed around 12-13 billion years ago.

Each star in the SASS group was once part of its own small galaxy that was later absorbed by the Milky Way. The rapid motion of these stars suggests that they came from primitive dwarf galaxies that later merged with our own. Unfortunately, the location of these dwarf galaxies that once contained the SASS stars is too faint to be studied in detail.

The discovery of SASS stars provides a new avenue for understanding the chemical evolution of stars in the early Universe. By studying the chemical evolution of these brighter SASS star analogues, researchers can gain insights into the formation and evolution of the Milky Way. The study of SASS stars could potentially reveal secrets about the early Universe that have remained hidden for billions of years.

The team behind the study has developed a new way to find SASS star analogues, making it easier for researchers to study these ancient stars without chasing the extremely faint SASS stars. This discovery opens up a whole new field of research, with the potential to revolutionise our understanding of the early Universe and the formation of galaxies.

As the search for SASS stars continues, we can look forward to uncovering more about the Universe's past and the role these ancient stars played in shaping the cosmos as we know it today.