# Interstellar comet 3I/ATLAS chemical analysis > Live situation record from CLSTR: https://clstr.news/situations/interstellar-comet-3iatlas-chemical-analysis > Updated: 2026-09-10T22:14:36.000Z. Sources: 9. Developments: 2. Astronomers studying the interstellar comet 3I/ATLAS, the third confirmed interstellar object detected, have identified chemical signatures suggesting it originated in an extremely cold environment. Initial observations from the William Herschel Telescope and the Very Large Telescope indicated large quantities of nitrogen and methanol, with formation temperatures estimated to be below –240°C. Research suggested the comet might be significantly older than our solar system, potentially twice its age. Subsequent analysis using the Atacama Large Millimeter/submillimeter Array (ALMA) revealed that the comet contains an unusually high amount of methanol and is the first interstellar object where scientists have detected deuterium. The concentration of deuterium in the comet’s water is reported to be more than 40 times higher than in Earth’s oceans and over 30 times higher than in comets from our own solar system. These findings provide critical clues regarding the chemical history and conditions of the distant star system from which the object was likely ejected. ## Timeline ### 2026-09-10: Interstellar comet 3I/ATLAS reveals unique chemical composition Astronomers using the ALMA telescope have discovered unique chemical compositions in the interstellar comet 3I/ATLAS, including high levels of methanol and the first recorded instance of deuterium in such an's. 2 sources. https://clstr.news/cluster/interstellar-comet-3iatlas-reveals-unique-chemical-composition ### 2026-09-08: Interstellar comet 3I/ATLAS shows signs of extreme cold and ancient origin Astronomers studying the interstellar comet 3I/ATLAS have discovered chemical signatures suggesting it formed in extreme cold and may be twice as old as our solar system. 7 sources. https://clstr.news/cluster/interstellar-comet-3iatlas-shows-unique-chemical-composition --- Cite as: Interstellar comet 3I/ATLAS chemical analysis. CLSTR, https://clstr.news/situations/interstellar-comet-3iatlas-chemical-analysis