The Pleiades star cluster is one of the prettiest sights in the night sky – a group of moderately bright stars that forms a tiny dipper. Depending on your eyesight and your sky conditions, you might see six or seven stars – or perhaps a few more.

But there’s far more to the Pleiades than that. The cluster contains more than a thousand known star systems. More than half of the systems have two or more stars. So the total number of stars may be close to two thousand – or perhaps a few more.

All of the stars were born in a single giant stellar nursery. The first probably were born about a hundred million years ago. The last flared to life millions of years later.

Some of the family members have wandered off – they’re no longer tied to the cluster. The remaining clump of stars spans about 80 light-years. The stars on the outskirts will be pulled away from the cluster by the gravity of the rest of the galaxy’s stars and gas clouds. Stars in the middle of the cluster are more tightly packed, so they’ll stick together longer – perhaps hundreds of millions of years.

This is a great time to look for the Pleiades. The cluster is well up in the east at nightfall. And two bright lights stand below it: the brilliant planet Jupiter and the star Aldebaran, to the right of Jupiter. The name “Aldebaran” means “the follower” – indicating that the bright star follows the Pleiades across the night.

And we’ll follow the Pleiades again tomorrow.

Script by Damond Benningfield