Is 3I/ATLAS older than Earth?
Can you guess how old 3I/ATLAS is? Well, it may be older than our Earth. Scientists say this comet has journeyed through space for billions of years, coming from a distant part of the Milky Way far before our Solar System
3I/ATLAS
3I/ATLAS is an interstellar comet, meaning it comes from outside our Solar System. NASA’s ATLAS telescope discovered it on 1 July 2025 in Chile. It travels very fast and recently passed close to the Sun
Unbound, Hyperbolic Orbit
Unlike planets, 3I/ATLAS follows a hyperbolic trajectory. This means its path is a wide arc that will send it away from the Sun for good. NASA confirms this orbit shows the comet arrived from beyond our Solar System
Possible Age of 3I/ATLAS
Based on NASA data and research compiled by astronomers, 3I/ATLAS likely formed in a region of our Milky Way called the thick disk. This region contains stars that are over 7 billion years old.
Older Than Earth and the Sun
Earth and the Sun are about 4.6 billion years old. Since 3I/ATLAS may come from the thick disk, its age is estimated to be at least 7 billion years. This makes it potentially older than our entire Solar System
Composition Reveals Its History
NASA’s James Webb and Hubble telescopes found 3I/ATLAS has an icy nucleus between 0.3 and 5.6 kilometres in size. It contains carbon dioxide, water ice, and other gases, showing it formed under different conditions than comets from our Solar System.
Why Knowing Its Age Matters
Studying 3I/ATLAS’s age helps scientists understand the early Milky Way galaxy. It carries material from before the Solar System’s formation. This helps answer questions about planet and star formation throughout the galaxy.
What Happens Next?
3I/ATLAS will continue moving away from the Sun and the Solar System. Scientists are observing it closely to learn more. Its ancient age makes it a valuable visitor from another time and place.
)
)
)
)
)