New Nature research suggests interstellar comet 3I/ATLAS may be a 12-billion-year-old relic from another planetary system, with carbon, nitrogen and hydrogen isotope ratios unlike those seen in Solar System comets — a chemical fingerprint from a world-forming environment that existed billions of years before the Sun.

An interstellar comet that passed through the Solar System last year did not come from here, and new measurements of what it is made of suggest it did not form anywhere recent either. The chemistry of 3I/ATLAS, published this week in Nature, points to a birthplace that was cold, distant, and old enough to predate [...] The post New Nature research suggests interstellar comet 3I/ATLAS may be a 12-billion-year-old relic from another planetary system, with carbon, nitrogen and hydrogen isotope rati