Interstellar comet reveals a cold birthplace far from stars rewriting early galaxy clues

Heavy hydrogen hints the comet formed in extreme cold

Scientists analyzing a newly spotted interstellar comet say its chemistry carries unusually high heavy hydrogen, pointing to an origin in a frigid, isolated corner of the Milky Way. The likely birthplace was far from other stars and may have existed before the Sun formed, offering fresh clues about conditions that shaped early planet formation.