Age-old problem

STARS can’t possibly have formed before the big bang, which is why astronomers have puzzled for decades over data that implies some stars are older than the Universe. “Even five years ago we had a factor of two uncertainty,” says Wendy Freeman of the Carnegie Observatories in California. Now new data from the Hubble Space Telescope has resolved the contradiction. Harvey Richer of the University of British Columbia says the measurements imply that the oldest stars formed about one billion years after the big bang, making the whole Universe just under 14 billion years old.