How old are the oldest stars? An international team of astronomers led by Dr. Anna Frebel of The University of Texas at Austin McDonald Observatory recently measured the age of an ancient star in our Milky Way galaxy at an extraordinary 13.2 billion years. This measurement provides a lower limit to the age of the universe and will help to disentangle the chemical history of our galaxy. Frebel’s results are published in today’s edition of The Astrophysical Journal Letters.
The team used radioactive decay dating techniques to date the star, called HE 1523-0901. This is close to the age of the universe of 13.7 billion years.