The Manger

Ancient astronomers, much more attuned to the sky than we are, saw a fuzzy spot in the sky and called it Praesepe, or Manger. Of course, the sky they saw is the same sky we see now, so let's look for this " Manger."

Northeast of the great red star Betelgeuse in Orion are the Gemini twins, Castor and Pollux. The brighter, yellow one is Pollux. And high in the eastern sky is the great mane of Leo the lion. The bright star at the base of this mane is Regulus, or " little king." Midway between Pollux and Regulus is a bright starlike object outshining them both. This is the planet Saturn. And just north of Saturn is our goal, the Manger: to moderns, the Beehive star cluster.

It is called the Beehive because that's just what it looks like through a pair of binoculars - a swarm of dozens of bees.

An open star cluster such as the Beehive is a group of stars, sometimes, as in the case of the Beehive or the Pleiades, numbering in the hundreds. Born at the same time from a tremendous cloud of hydrogen gas, they are now caught in one anotheršs gravitational grip, circling each other as they move together through space.

How old is the Beehive? Though magnificent as a whole, the cluster contains no really bright stars. Brighter stars die first, so insatiable is their appetite for fuel. All the stars with lifetimes of four hundred million years or less are absent from this cluster.

We assume that originally the cluster contained stars of all brightness -- of all lifetimes -- and the brightest ones have already died. The Beehive cluster was born before the first dinosaurs lived on the Earth -- four hundred million years ago.

(02/01/06)