The Sun is four and a half billion years old – a third of the age of the universe. Compared to the stars in globular clusters, though, it’s a youngster. Those stars were born when the universe was young.

An example is Messier 3 – a family of about half a million stars. The cluster is about 11.4 billion years old. That means its stars were born just a couple of billion years after the Big Bang.

All of the cluster’s remaining original stars are fainter and less massive than the Sun. Anything heavier than the Sun has exhausted its nuclear fuel, leaving only a corpse – a small, dense, faint remnant. And astronomers have seen quite a few of these remnants in M3. But the dead stars are tough to find inside the crowded cluster.

Some of the stars of Messier 3 are more massive than the Sun. But they weren’t born that way. Instead, they’ve grown by cannibalizing companion stars.

Some of them have pulled gas off the surface of a companion. Others have merged with a companion. Either process adds to a star’s mass. That makes the star brighter and bluer – making it look a lot younger that it really is.

This huge cluster of ancient stars is about 34,000 light-years away. It’s in the constellation Canes Venatici, the hunting dogs. M3 isn’t quite bright enough to see with the eye alone, but it’s an easy target for binoculars. It’s well up in the east at nightfall, above the bright star Arcturus.

Script by Damond Benningfield