Cancer, the crab, is famed for its position in the zodiac. Yet other than its location, there’s not much to recommend it. The outline of the crab itself isn’t all that crab-like, and even its brightest stars are mere pinpricks of light.
Cancer’s main highlight is a star cluster known as Messier 44. Astronomer Charles Messier added it to his catalog of astronomical objects 250 years ago.
M44 buzzes with so many tightly packed stars that it’s also known as the Beehive. That appearance isn’t deceiving, because M44 is one of the busiest clusters around, with a thousand stars or more.
The cluster is about 600 light-years away, and probably about 600 million years old. Astronomers deduced its age by determining the types of stars it contains — and the types it does not. Missing are the hottest, brightest, and most massive stars. Such stars burn through their nuclear fuel in a hurry, so they disappear quickly, placing a limit on the cluster’s age.
Most of the cluster’s members are the faint embers known as red dwarfs, while about a third are somewhat like the Sun. And only a handful of stars are much brighter and more massive than the Sun.
M44 is low in the eastern sky at first light tomorrow. It might be a bit tough to see, though, because the Moon is passing directly in front of it, blotting out some of its stars. Even so, binoculars reveal several stars, adding a bit of sparkle to the otherwise drab crab.
Script by Damond Benningfield