A group of ancient stars has been found near the sun. This discovery could change what we know about the Milky Way. Scientists used the Gaia space telescope to study these stars. They found that our part of the Milky Way might be much older than we thought.
The Milky Way is our galaxy. It has more than 100 billion stars. Most of these stars, including our sun, are in a thin disk. This disk rotates around the centre of the galaxy. Scientists believe this disk formed about 8 to 10 billion years ago. However, the new study shows some stars in this disk are more than 13 billion years old.
How They Found the Stars
Researchers used data from the Gaia space telescope. Gaia is a mission by the European Space Agency. It collects data about stars in our galaxy. The team looked at more than 800,000 stars near the sun. This area is about 3,200 light-years around the sun. For comparison, the Milky Way is about 100,000 light-years wide.
The team used machine learning to study the data. They measured the age and metal content of the stars. Metal content helps scientists understand how old a star is. Older stars have less metal because they formed when the universe had fewer heavy elements.
What They Found
The ancient stars they found formed less than a billion years after the Big Bang. The Big Bang happened about 13.8 billion years ago. This means these stars are almost as old as the universe itself. The presence of these stars in the thin disk suggests that this part of the Milky Way formed much earlier than we thought.
Why It Matters
This discovery is important for several reasons. First, it changes our understanding of the Milky Way’s history. Scientists now think the thin disk started forming about 4 to 5 billion years earlier than they believed. This means the Milky Way’s star formation timeline is much longer.
Second, it helps scientists understand how galaxies form and evolve. They can learn more about the early universe by studying these ancient stars. This can also help them understand other galaxies.
The Future of This Research
Scientists are excited about this discovery. They plan to continue studying these ancient stars. They want to create detailed maps of the Milky Way. These maps will show the age, chemical composition, and movement of its stars. This will help them piece together the history of our galaxy.
The Gaia mission will continue to collect data. Future studies will use this data to learn even more about the Milky Way. Scientists hope to find more ancient stars and learn about their origins.
The discovery of ancient stars near the sun is a big step forward in understanding the Milky Way. Our galaxy is older than previously thought, which will help scientists learn more about the early universe and galaxy formation.
