Corvus the Crow is a small constellation hiding a fabulous galaxy collision and a planetary nebula at its center.
Corvus the Crow has an interesting mythological story. Part of the story can be found with Crater the Cup and Hydra the Water Snake, when lazy Corvus took too long to quench Apollo's thirst. But a second story about Corvus the Crow involves how crows got their black color. According to legend, Corvus was a white bird until he brought back bad news to Apollo. Apollo had asked Corvus to spy on his lover, Coronis. When Corvus reported back to Apollo that Coronis had been unfaithful, Apollo took his anger out on the crow and turned his feathers to black.
You can find Corvus just southwest of the bright star Spica in Virgo. Its brightest star in magnitude 2.59 Gienah, or Gamma Corvi. Gienah lies 165 light-years away. The four brightest stars in the constellation form a crooked square. The second brightest star in the Crow is in the opposite corner: magnitude 2.65 Beta Corvi, lying 140 light-years away. In the northeast corner is magnitude 2.94 Algorab, or Delta Corvi. Algorab lies about 88 light-years away. The last corner is marked by magnitude 3.02 Epsilon Corvi, lying 303 light-years away.
Two other small stars of note reside in the constellation Corvus the Crow. Less than a half degree from Algorab is magnitude 4.3 Eta Corvi, which lies about 60 light-years away. Directly below Epsilon is Alchiba, or Alpha Corvi, at magnitude 4.01. Alchiba lies 48 light-years away. This constellation serves as proof that the Alpha star in a constellation is not always the brightest, or even one of the brightest.
There is one main reason amateur observers usually turn their telescopes toward Corvus, and that is for the galaxy pair NGC 4038 and NGC 4039. This pair of colliding galaxies is known as the Antennae Galaxy, or sometimes the Ringtail Galaxy. The Antennae are located on the western side of the constellation and register as a magnitude 10.7. Dark skies and a telescope of at least 4 inches are required to view it.
These interacting galaxies were first discovered by Sir William Herschel on February 7, 1785. At the time galaxies were still unknown, so they were originally classified as nebulae.
One other object of note is the planetary nebula NGC 4361. This 10th magnitude round glow lies within the crooked square of Corvus. A 4- to 6-inch telescope is a good place to start to try to pick up the nebula, and higher powers will increase your odds of finding it and the 13th magnitude star that lies within.
