{"id":26792,"date":"2025-07-12T18:32:55","date_gmt":"2025-07-12T22:32:55","guid":{"rendered":"https:\/\/stateofthenation.info\/?p=26792"},"modified":"2025-07-12T18:35:25","modified_gmt":"2025-07-12T22:35:25","slug":"comet-3i-atlas-a-rare-interstellar-object-tracing-out-an-unusual-trajectory-that-is","status":"publish","type":"post","link":"https:\/\/stateofthenation.info\/?p=26792","title":{"rendered":"

COMET 3I\/ATLAS: A Rare Interstellar Object Tracing Out An Unusual Trajectory That Is…..<\/b><\/h2>"},"content":{"rendered":"

…Hyperbolic Rather Than Elliptical With An
\nEccentricity Of About 6 And Not Bound To
\nThe Sun.<\/strong><\/h2>\n

<\/p>\n

Comet 3I\/ATLAS<\/h1>\n

Posted at science.nasa.gov<\/p>\n

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\"This<\/a><\/figure>\n
This diagram shows the trajectory of interstellar comet 3I\/ATLAS as it passes through the solar system. It will make its closest approach to the Sun in October.<\/div>\n
NASA\/JPL-Caltech<\/div>\n<\/div>\n<\/div>\n<\/div>\n

Discovery<\/h2>\n

The NASA-funded\u00a0ATLAS<\/a>\u00a0(Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, first reported observations to the Minor Planet Center of comet 3I\/ATLAS on July 1, 2025. Since the first report, observations made before the discovery were gathered from the archives of three different ATLAS telescopes around the world and Caltech\u2019s Zwicky Transient Facility at the Palomar Observatory in San Diego County, California. These \u201cpre-discovery\u201d observations extend back to June 14.<\/p>\n

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\"This<\/a><\/figure>\n
This animation shows the observations of comet 3I\/ATLAS when it was discovered on July 1, 2025. The NASA-funded ATLAS survey telescope in Chile first reported that the comet originated from interstellar space.<\/div>\n
Credit: ATLAS\/University of Hawaii\/NASA<\/div>\n<\/div>\n<\/div>\n<\/div>\n

Overview<\/h2>\n

Comet 3I\/ATLAS is the third known object from outside our solar system to be discovered. Astronomers have categorized this object as interstellar because of the hyperbolic shape of its orbital path. (It does not follow a closed orbital path about the Sun.) When the orbit of 3I\/ATLAS is traced into the past, the comet clearly originates from outside our solar system.<\/p>\n

Comet 3I\/ATLAS poses no threat to Earth and will remain far away. The closest it will approach our planet is about 1.8 astronomical units (about 170 million miles, or 270 million kilometers). 3I\/ATLAS will reach its closest point to the Sun around Oct. 30, 2025, at a distance of about 1.4 au (130 million miles, or 210 million kilometers) \u2014 just inside the orbit of Mars.<\/p>\n

The interstellar comet\u2019s size and physical properties are being investigated by astronomers around the world. 3I\/ATLAS should remain visible to ground-based telescopes through September 2025, after which it will pass too close to the Sun to observe. It will reappear on the other side of the Sun by early December 2025, allowing for renewed observations.<\/em><\/p>\n

How This Comet Got Its Name<\/h2>\n

Comets are generally named for their discoverer(s), in this case the ATLAS survey team. The letter \u201cI\u201d is for \u201cinterstellar,\u201d indicating that this object came from outside our solar system. It\u2019s the third known interstellar object, hence the \u201c3\u201d in the name.<\/p>\n

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