Astronomers from the University of Bologna and Leibniz Institute for Astrophysics have used 200,000 ancient stars to estimate the Universe's age at 13.6 billion years. This groundbreaking research addresses the long-standing Hubble tension by providing a new method to measure cosmic age through stellar data rather than traditional expansion rate calculations.

Using the European Space Agency's Gaia mission data, researchers analyzed stellar ages with unprecedented precision. The team developed a catalog containing age estimates for over 200,000 Milky Way stars, then carefully selected about 100 of the oldest and most reliable measurements. This approach provides a robust lower limit for the Universe's age since it cannot be younger than its oldest stars.

The findings support the older age estimated from cosmic microwave background measurements rather than the younger age suggested by Cepheid variable stars and supernovae observations. This adds crucial evidence to the Hubble tension debate, which questions whether different measurement methods are capturing the same cosmic expansion rate or if fundamental physics needs revision.