Praesepe is an
open star cluster located within the constellation
Cancer, the Crab. Its name is Latin, meaning both "
manger" and "crib". Another common name for this cluster is the
Beehive Cluster, and it's been cataloged as M44 or NGC2632.
Praesepe is a large cluster, spanning the size of two to three
full moons, and is easily visible to the unaided eye on dark, clear nights. Still, the best view of the cluster would probably be through binoculars or a small telescope.
The cluster lies more than 500
light years distant and has an estimated age of about 400 million years. Because of this, it's been mentioned in many ancient socities and literature.
It was seen by the Japanese in ancient times as
a lump of souls in the sky and the sight terrified them. To others, it was thought to be the a gate or portal through which souls descended upon
Earth to be born. It's also been thought to forecast the weather, particularly if a storm would be coming or not.
Within the cluster lie two of the main stars of the constellation Cancer, gamma Cancri (
Asellus Borealis) and delta Cancri (Asellus Australis), meaning Southern Ass or Donkey and
Northern Ass or Donkey. These two donkeys feed off the manger, and are thought to have been the donkeys the god
Dionysus and
Silenus rode on during their battle with the Titans, who were startled by the animals, causing the gods to win. They were placed in the sky as a reward.
The star cluster was first recorded by
Hipparchus in 130 B.C. He identified it as a "cloudy star". Later,
Ptolemy notes it as one of the seven nebulae in his work,
Almagest. Around 1600,
Johann Bayer also mentioned it in his star chart as
Nubilum, or "cloudy object". It wasn't until
Galileo pointed his telescope at the cluster that it was realized not to be a
nebula at all, but rather a cluster of a hundred stars or more.
It has been speculated that the star cluster once had a common origin with the star cluster
Hyades in the constellation
Taurus. The age and direction of motion of Praesepe coincide with Hyades, and the
stellar contents and spatial motions of the clusters are very similar.
If nothing else, Praesepe is a beautiful and worthwhile object that can be easily viewed in the night sky and can be seen and
appreciated with little to no special equipment.