Interstellar Comet 3I/ATLAS Rapidly Accelerating Through Solar System
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| Image Credits: NASA, ESA, David Jewitt (UCLA); Image Processing: Joseph DePasquale (STScI) |
Discovered on July 1, 2025, by the Asteroid Terrestrial‑impact Last Alert System (ATLAS) survey telescope in Chile, 3I/ATLAS was identified as the third confirmed object of interstellar origin to traverse the solar system, following 1I/ʻOumuamua and 2I/Borisov.
Early measurements indicate the object is unusually large for an interstellar visitor, with estimates around 5 to 11 kilometres in diameter.
As 3I/ATLAS approaches perihelion, the point of closest approach to the Sun on October 29, 2025, observations show it becoming increasingly active.
Researchers report a growing dust and gas tail, and a jet of material being expelled in the direction of the Sun.
Spectroscopic studies deploying the James Webb Space Telescope and the Hubble Space Telescope have revealed that the comet’s composition includes abundant carbon dioxide ice relative to water ice, a high CO₂/H₂O ratio that deviates from typical solar system comets.
A coordinated observation campaign involving multiple spacecraft, including Mars orbiters and others potentially aligned with the comet’s tail, aims to gather data on the interstellar visitor.
According to the European Space Agency and other agencies, several probes such as the Juice mission could observe 3I/ATLAS when it passes Jupiter’s orbit in early 2026.
While many scientists and social media users have speculated on non-natural origins as the majority of scientists involved with the data treat 3I/ATLAS as a naturally occurring interstellar comet, albeit with curious chemical signatures and structural behaviour notable for a visitor from beyond.
The comet’s trajectory assures that it will not pose any risk to Earth or the planets. Its path, moving at high speed and on a steeply inclined orbit, will carry it back out of the solar system after its sunward passage.
