Corvus and Coma Berenices

Advertisement

One of my favorite constellations is Corvus the Crow, which is visible during spring. It is compact and fairly bright, making it easy to locate. Without too much imagination, you can see a crow winging his way across our southern sky.

Corvus is composed of four main stars of nearly equal brightness, forming the shape of a small kite or cross. In fact, it is sometimes confused with a similar, more famous group of stars called the Southern Cross, which is not visible from our mid-northern latitude.

To locate Corvus the Crow, begin with the Big Dipper, which is easy to spot almost directly overhead at 9:30 p.m. If you trace an imaginary arc through the stars of the Big Dipper's curved handle and continue along that same arc, you will first arrive at the bright orange star Arcturus. From Arcturus, stretch your imaginary line straight to the bright blue star Spica. Finally, continue in the same line past Spica and you will arrive at the kite-shaped constellation of Corvus, about a third of the way up in the southern sky. Use this old saying to help remember the directions to Corvus: "Follow the arc to Arcturus, spike on to Spica, and continue to Corvus."

At the upper right and lower left of the kite-shaped pattern are the stars Gienah and Kraz, marking the wing tips of the Crow. Minkar, the star at the lower right, marks the Crow's head. The fainter star just below Minkar is Alchiba, the Crow's beak. Algorab, at the top left, completes the pattern as the Crow's tail.

The Roman poet Ovid reported that Corvus the Crow represents the beloved pet bird of Apollo, the sun god of Greek mythology. Apollo sent Corvus on a mission to spy on his true love, Coronis, and report back to him, but when the beautiful silver bird reported to Apollo that Coronis had been unfaithful, Apollo, in his anger, cursed the bird so severely that his silvery feathers turned jet black.

See if you can spot the celestial crow Corvus this spring. Just "follow the arc to Arcturus, spike on to Spica, and continue to Corvus."

There are a number of star clusters visible to the unaided eye, such as the well-known Pleiades and the Beehive clusters, but there is only one star cluster that makes a constellation all by itself. You can see it directly overhead on May evenings as a smattering of a dozen or so faint stars. This is the constellation we call Coma Berenices, and it is one of only a few constellations associated with a real person rather than a mythological one.

On ancient star charts, this star cluster is shown as representing the tuft of hair on the end of the tail of the nearby lion Leo, but in 1602, astronomer Tycho Brahe designated it as a distinct and separate constellation. Legend has it that the constellation represents the hair of Egyptian Queen Berenice, who cut it off to fulfill a vow made to the goddess Aphrodite that she would return her husband, King Ptolemy III, safely from battle. Her beautiful hair was clipped off and placed in Aphrodite's temple as an offering, but the golden tresses mysteriously disappeared overnight. For some reason, the king suspected that the court astronomer, Conon of Samos, was responsible, and when questioned, the quick-thinking astronomer pointed to the unnamed star cluster and explained that Aphrodite had placed the beautiful tresses in the sky for all to see for eternity. Apparently, the king was satisfied with this explanation and spared the astronomer's life. So, Leo loses a tail, but we gain Queen Berenice's hair.

When you gaze up at Coma Berenices tonight, consider that you are looking straight up out of the top of our pancake-shaped Milky Way galaxy into the depths of intergalactic space. The band of the Milky Way encircles you along the horizon. Large telescopes have revealed a cluster of more than 3,000 galaxies, far beyond the stars of our little constellation, at a distance of 280 million light years. What we really have, then, is a cluster within a cluster, disguised as Berenice's beautiful hair.

Comments

Use the comment form below to begin a discussion about this content.

Requires free registration

Posting comments requires a free account and verification.