From the July 2008 issue

With lots of elements like uranium, how can the star HE 1523-0901 be 13.2 billion years old?

Patrick E. Wondra, Pennington, Minnesota
By | Published: July 28, 2008 | Last updated on May 18, 2023
Prior to HE 1523-0901’s birth, supernovae produced heavy elements like uranium, europium, and thorium by a process called neutron capture. So, HE 1523-0901 formed from gas that already was enriched in these heavy elements.