An article published in the journal “Nature Astronomy” reports the results of a study on the interstellar comet 3I/ATLAS, which indicate that it formed in a much colder environment than the solar system. This conclusion was reached by a team of researchers led by Luis E. Salazar Manzano, a Ph.D. student at the University of Michigan, using observations conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) radio telescope. Specifically, the Atacama Compact Array (ACA) revealed a ratio of so-called semi-heavy water to ordinary water at least 30 times higher than that found in solar system comets and over 40 times higher than that found in Earth’s oceans. Such an enrichment of water with so many deuterium atoms can only occur in very cold environments, around 30 Kelvin.