Comet 3I/ATLAS originated around a star twice as old as the Sun

The interstellar comet 3I/ATLAS has been found to be more than twice the age of the Sun, according to a study published in Nature Astronomy. Using the Very Large Telescope (VLT) of the European Southern Observatory (ESO), astronomers measured isotopic ratios in the comet's gas, revealing it formed around an ancient, low-metallicity star that existed when the universe was much younger.

Chemical fingerprints

The team, led by Cyrielle Opitom (University of Edinburgh), analyzed carbon and nitrogen isotopes in cyanide molecules surrounding the comet. These ratios are significantly higher than those seen in solar system comets, indicating a different origin. "A diferencia de los cometas de nuestro Sistema Solar, este visitante interestelar lleva proporciones isotópicas inusualmente altas de carbono y nitrógeno," said co-author Aravind Krishnakumar (University of Liège) Source: Clarín. The isotopic signatures are sensitive to the environment of formation and remain largely unchanged during the comet's journey.

Ancient origins

The findings suggest 3I/ATLAS formed in the outer regions of a star with low metallicity—few heavy elements—pointing to a star that formed billions of years before our Sun. "3I/ATLAS es una oportunidad realmente emocionante para investigar la composición de otro sistema planetario, uno que se formó mucho antes de que existieran nuestro Sol y nuestro Sistema Solar," noted co-author Rosemary Dorsey (University of Helsinki) Source: Infobae. Other analyses indicate the comet could be up to 12 billion years old.

This interstellar visitor, the third detected after 1I/ʻOumuamua and 2I/Borisov, is the brightest comet of its kind, allowing detailed study. Its composition offers a window into planetary formation in the early universe.