Anomalous Isotopic Signatures in Interstellar Comet 3I/ATLAS Point to an Ancient, Metal-Poor Milky Way Origin

To the point

3I/ATLAS, an interstellar comet, exhibits water with unusually high deuterium and strange carbon isotope ratios in CO2 and CO that indicate it formed in extremely cold, metal-poor conditions over 10 billion years ago and is a preserved fragment of an ancient planetary system, providing evidence that icy planetesimals formed early in the Milky Way, a conclusion drawn by researchers including Martin Cordiner, Nathan X. Roth, Marco Micheli, and Geronimo Villanueva.