Interstellar comet's ancient chemistry reveals secrets of universe's 'cosmic noon'

From the cold depths of intergalactic space, a comet designated 3I/Atlas has crossed into our solar system carrying chemical memories of a universe that existed ten to twelve billion years ago. Formed during 'cosmic noon'—the universe's most fertile era of star creation—this ancient traveler bears a composition so foreign to our own cosmic neighborhood that scientists describe it as belonging to an entirely different branch of the universe's family tree. Its extraordinary abundance of deuterium and scarcity of heavier elements speak to a time before the universe had accumulated the chemical ri