Comet 3I/Atlas
10 months ago
- #astronomy
- #comets
- #interstellar
- Comet 3I/ATLAS was discovered by NASA-funded ATLAS survey telescope in Chile on July 1, 2025.
- It is the third known interstellar object, originating from outside our solar system.
- The comet follows a hyperbolic trajectory, meaning it does not orbit the Sun and will leave the solar system.
- Closest approach to Earth is 1.8 astronomical units (170 million miles) and to the Sun is 1.4 au (130 million miles) around Oct. 30, 2025.
- Astronomers are studying its size and physical properties; it remains visible through September 2025 before solar interference.
- Named after the ATLAS survey team, with 'I' for interstellar and '3' indicating it's the third such object discovered.
- Formed in another star system, it has been drifting through space for millions or billions of years.
- Its trajectory and speed confirm its interstellar origin; it moves at 137,000 mph (221,000 kph).
- No threat to Earth; closest approach is 1.6 au (150 million miles).
- Previous interstellar objects include 'Oumuamua (2017) and 2I/Borisov (2019).