<\/p>\n As 3I\/ATLAS<\/a> approached the sun<\/a> and sunlight warmed its icy surface, it released gas and dust, forming a glowing halo \u2014 or coma \u2014 around its core, which allowed ALMA to analyze the comet’s chemical composition in detail.<\/p>\n Article continues below <\/p>\n You may like<\/p>\n The measurements show that methanol is far more abundant, relative to hydrogen cyanide, than astronomers typically see in comets from our own solar system<\/a>. That chemical imbalance suggests 3I\/ATLAS likely formed in a planetary system with very different physical conditions \u2014 such as colder temperatures and\/or a different chemical inventory \u2014 than the one that produced our own comets, according to a statement<\/a> from the National Radio Astronomy Observatory (NRAO).<\/p>\n “Observing 3I\/ATLAS is like taking a fingerprint from another solar system,” Nathan Roth, lead author of the study and a professor at American University, said in the statement. “The details reveal what it’s made of, and it’s bursting with methanol in a way we just don’t usually see in comets in our own solar system<\/a>.”<\/p>\n Methanol \u2014 which is used for industrial purposes here on Earth, in contrast to the drinkable ethanol \u2014 isn’t rare in space. It forms on the surfaces of icy dust grains in interstellar clouds and is commonly incorporated into comets during planet formation. But the amount detected in 3I\/ATLAS appears unusually high compared with the ratios seen in solar system comets, making the object a valuable chemical “fingerprint” from another planetary system.<\/p>\n Discovered in July 2025 by the Asteroid Terrestrial-impact Last Alert System, 3I\/ATLAS is only the third known object confirmed to have entered the solar system from interstellar space. The first was ‘Oumuamua<\/a>, spotted in 2017, followed in 2019 by 2I\/Borisov<\/a>, which displayed a more traditional comet-like appearance.<\/p>\n Since 3I\/ATLAS’ discovery, telescopes around the world \u2014 including the Hubble Space Telescope<\/a> and the James Webb Space Telescope<\/a> \u2014 have been monitoring the comet as it travels through the inner solar system. Images show a diffuse coma and faint dust tail created as sunlight heats the comet’s ices, releasing gas and dust into space.<\/p>\n Those outflows also help explain another phenomenon observed around the comet: a vast cloud of gas glowing in X-rays as charged particles from the solar wind<\/a> slam into material escaping from the nucleus. The ALMA observations further revealed that hydrogen cyanide mostly streams directly from the comet’s nucleus, while methanol is released both from the nucleus and from icy grains in the coma<\/a> acting like miniature comets \u2014 the first time such detailed outgassing behavior has been mapped in an interstellar object, according to the statement.<\/p>\n \n A Hubble Space Telescope image of comet 3I\/ATLAS. (Image credit: NASA\/ESA\/David Jewitt (UCLA)\/ Image Processing: Joseph DePasquale (STScI))<\/p>\n The arrival of a new interstellar object has also fueled speculation online<\/a>, including suggestions that 3I\/ATLAS could be artificial in origin. But the growing body of evidence \u2014 including its comet-like tail, gas jets and molecular composition \u2014 strongly indicates that the object is a natural icy body.<\/p>\n For astronomers, that’s the real excitement. Objects like 3I\/ATLAS act as messengers from other planetary systems, preserving the chemical conditions present where they formed billions of years ago \u2014 and offering rare opportunities to study the building blocks of distant worlds<\/a> without ever leaving our own solar system.<\/p>\n![\"A](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2025\/09\/Sye7gV5yuME9CoKuHsW8ge.jpg\")
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