By Ron Cowen
For elderly stars, the fountain of youth may be only a collision away.
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2003/03/2487.jpg?resize=150%2C140&ssl=1)
Evidence for the rejuvenating power of collisions comes from studying bright, young-looking stars residing in globular clusters, the oldest stellar groupings in the Milky Way. For nearly 50 years, astronomers examining globular clusters have encountered a paradox. Even though massive stars go for the gusto, burning brightly and dying out in just a few million years, several keep on shining in the dense cores of these clusters, which may be as old as 16 billion years.