News: NASA confirmed water’s chemical fingerprint on interstellar comet 3I/ATLAS, reshaping ideas on comet evolution and ingredients for life.
About Interstellar Comet 3I/ATLAS
- 3I/ATLAS is an interstellar comet – the third known object from outside our solar system.
- Naming: The prefix “3I” marks it as the third confirmed interstellar object after:
- 1I/ʻOumuamua– identified in 2017 (was dry))
- 2I/Borisov – identified in 2019 (was rich in carbon monoxide- rich)
- Identified by: It was identified by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Hawaii.
- Origin: It entered our Solar System from another star system and is estimated to be at least seven billion years old.
- Trajectory: It is travelling on a hyperbolic path.
- Speed: It travels at a speed of 57–68 km/s.
- Composition:
- It is an active comet with a solid icy nucleus and a coma of gas and icy dust escaping from the nucleus.
- NASA’s Swift Observatory detected hydroxyl gas formed when sunlight breaks water molecules.
- It was losing water at a rate of roughly 40 kilograms per second, even though it was far beyond the typical distance where solar heat could cause water ice to vaporise.
- It is an active comet with a solid icy nucleus and a coma of gas and icy dust escaping from the nucleus.
- Its estimated nucleus size is 10–30 km, larger than earlier interstellar comets.
- No threat: It poses no threat to Earth and will remain far away.
- The closest it will approach earth is about 1.8 astronomical units (about 170 million miles, or 270 million kilometers).
- Significance: The water signature suggests distant planetary systems may share chemistry with earth’s, informing models of comet and planet formation.
