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Figures Formed by Constellations

Constellation figures are human interpretations applied to arrangements of stars, connected like dots to form imaginary figures. Since antiquity, sky-watching cultures have noted the shifting appearance of star patterns and associated these with changes in the planting and harvest seasons. Constellation figures, therefore, were probably first important for agricultural reasons. Given names and personified as gods, humans or animals, constellation figures also became elements of mythology. Cultures on all continents watched the same stars and envisioned very different constellation figures appropriate to their unique mythology, agricultural seasons and spiritual practices. In 150 A.D., the Greek scientist Ptolemy cataloged 1,022 stars and arranged them into 48 constellations. New constellations have been added and others subtracted over the centuries. In 1922, the International Astronomical Union adopted a list of 88 constellations drawn entirely from ancient Greek and Roman traditions. Constellation figures on the list are grouped according to the time of year in which they are visible in the heavens. Each season has its superstars.

Winter
- Taurus, "The Bull," is a constellation figure believed to be named to honor the Greek myth of Europa and the bull. The v-shaped horns of Taurus are easy to spot in winter and spring in the northern hemisphere. The star cluster Pleiades and the supernova Crab Nebula are two points of interest that compose this constellation figure.
Spring
- Centaurus is one of the largest constellation figures, most visible in the northern hemisphere during the month of May. It represents Chiron, the half-man, half-horse figure of Greek mythology known as a Centaur. It's also perhaps the clearest constellation figure: Against a dark sky, it doesn't take much imagination at all to pick out the centaur's equestrian outline. Centaurus is the closest constellation figure to Earth and includes Earth's nearest star, Alpha Centauri, among its outline.
Summer
- Sagittarius, "The Archer," was the God of War in ancient Babylon. It's believed that the Babylonians gave his name to this constellation figure visible most of summer in the northern hemisphere and during winter in the southern hemisphere. Legend says he was placed in the sky to guide the Argonauts on their ocean voyages. But astronomers have long used Sagittarius as an important reference point, too, because it marks the direction of the center of the Milky Way. Sagittarius covers a lively portion of the Milky Way that includes four open star clusters and three nebulae.
Fall
- Cassiopeia, "The Queen," is the mother of Andromeda. In Greek myth, she was chained to her throne for being boastful of her beauty. The nearest constellation figure to the Big Dipper, she's at her brightest in November but can be glimpsed in the northern sky all year round. As the constellation rotates and the figure inverts during the year, Cassiopeia is said to be hung upside down as punishment for her vanity. This constellation figure is one of Ptolemy's original 48.

Astronomy