The mysterious interstellar comet 3I/ATLAS is probably the oldest comet ever observed. Its age may exceed the age of the Solar System by more than 3 billion years.
3I/ATLAS was discovered in early July. It became only the third confirmed object in history to arrive in the Solar System from interstellar space. The comet will pass perihelion on October 29, 2025, after which it will begin to move away from the Sun.
Unlike the two previous interstellar objects that entered our Solar System from other parts of space, 3I/ATLAS appears to be moving through the galaxy on a trajectory that suggests it originated from the Milky Way’s “thick disk.” This is the name given to clusters of ancient stars rotating above and below the thin plane where the Sun and most stars are located.
This opens up a very interesting opportunity. According to astronomers at Oxford University, there is a fairly high probability (estimated at two to three) that 3I/ATLAS is significantly older than our Solar System. Statistical analysis shows that it probably formed around an old star from the “thick disk”, and its age may be 7.5 billion years or even more. This makes 3I/ATLAS radically different from comets in our Solar System, which cannot be older than 4.5 billion years.
According to scientists, 3I/ATLAS is rich in water ice. As it approaches the Sun, its light will heat the surface of the interstellar comet and cause the material to sublimate, resulting in the formation of a glowing coma around it, as well as a tail.
If the results of the study are confirmed, this could have important implications for how many interstellar objects can be detected by next-generation telescopes, such as the Vera Rubin Observatory, which recently began observations. This may also provide clues about the role that ancient interstellar comets play in the formation of stars and planets throughout the galaxy.
According to Phys.org
