Farewell To 2025: A Year When An Interstellar Visitor Became Global Obsession

3I/ATLAS passed closest to Earth on December 19 at a safe distance of 269 million kilometres.

22 Dec 2025, 17:55 · www.ndtv.com

2025 has come to an end, and out of various events, the world will remember this year for one particular celestial event - the discovery and frenzy surrounding 3I/ATLAS, the third confirmed interstellar object to enter our solar system after 'Oumuamua (2017) and 2I/Borisov (2019). Because of its mysterious nature, this rare visitor from beyond our cosmic neighbourhood sparked a global obsession.

3I/ATLAS was discovered this year on July 1 by the NASA-funded ATLAS survey. It initially appeared as a faint, blue-green dot moving rapidly through the skies, and its hyperbolic orbit confirmed it was an interstellar traveller from a distant star system.

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Many experts, including Harvard physicist Avi Loeb, raised questions about 3I/ATLAS and pointed out anomalies, fueling speculation about its origins, with some even suggesting that the object doesn't look natural and could be of extraterrestrial origin. But when NASA shared its images taken by space telescopes, it clearly referred to it as a 'comet', debunking various theories.

NASA confirmed that 3I/ATLAS, which passed closest to Earth on December 19 at a safe distance of 269 million kilometres, has an icy nucleus and a coma, consisting of a bright cloud of gas and dust that surrounds the comet and is emitted at increasing rates as the comet approaches the Sun.

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As mentioned earlier, it didn't follow a closed orbital path around the Sun and had a hyperbolic trajectory, which means it moved too fast to be bound by the Sun's gravity.

3I/ATLAS approached from the direction of the constellation Sagittarius, where the central region of our galaxy is located. The same region from where the "Wow!" signal was detected in 1977, a short-lived, yet extremely powerful radio burst that looked like a potential sign of extraterrestrial intelligence (SETI). It remains a mystery.

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The object is just passing through our solar system and will exit soon, but scientists will keep probing where it exactly came from and where it went (after it leaves our solar system). The entire saga highlights humanity's fascination with the unknown and our desire to explore the cosmos.

While the object itself may be a natural comet, the kind of frenzy it caused will definitely inspire future generations of scientists and astronomers. The comet will surely have a long-lasting impact on all of us.

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