There are quite a few varieties of birds portrayed among the constellations. There is a swan, an eagle, a dove, a crane, a toucan, a peacock, a bird of paradise and even a mythical phoenix.
Over toward the south as night falls these spring evenings is yet another: Corvus, the Crow.
Next to the famous Sickle of Leo, Corvus is probably the most striking star pattern in the spring southern sky for those living at mid-northern latitudes. It appears as a small, moderately bright quadrilateral-shaped pattern of stars; like a triangle whose top has been removed by a cut that slants from upper left to lower right. Add a fainter adjoining star and the pattern resembles the battered mainsail of a Chinese junk.
Corvus can also be used to positively identify the bluish first-magnitude star Spica, in Virgo. Just follow the direction of Corvus' slanting top to the east (to the left) and you will soon arrive at Spica.
A snaky tale
Corvus is supposed to represent the unfaithful raven of the god Apollo.
The bird was sent out with a cup for some water, but instead loitered at a fig tree until the fruit became ripe. He then returned to Apollo without the cup, but with a water snake in his claws, alleging the snake to be the cause of his delay.
As punishment, the angry Apollo changed Corvus from silvery-white to the black color that all crows and ravens bear to this day. In addition, Corvus was forever fixed in the sky along with the Cup (Crater) and the Snake (Hydra), doomed to everlasting thirst by the guardianship of the Hydra over the Cup and its contents.
Crater, the Cup is a small and rather faint figure, which corresponds quite closely to its name. Its stars outline a goblet, but unfortunately they're hard to distinguish when the sky is hazy or when there's a bright Moon in the sky.
Where's the Cross?
A couple of weeks ago we highlighted Crux, the famous Southern Cross. Interestingly, when the four-sided Corvus has reached its highest point in its course across the sky which this week roughly corresponds to around 9:30 p.m. local daylight time it stands directly above the Southern Cross, which is also attaining its highest point above the South Pole of the sky.
But as we also noted, even at its highest, the Cross remains out of sight below the horizon everywhere in the contiguous United States except for the Florida Keys and the southernmost tip of Texas. (Hawaiians also get a good view of Crux.)
Thus Corvus reveals the position of a constellation whose name is known to almost everyone though invisible to many of us.
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Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York.