By Jim Kaler

Eighty-eight formal constellations, named patterns of stars, spread across the sky. Fifty were handed down from the ancients, while another 38 were added in modern times by explorers of the southern hemisphere and to fill in the blanks up north. Countless informal asterisms are scattered among them. Three are icons: the Big Dipper (part of Ursa Major, the Great Bear), the Southern Cross, and one of the most recognizable sights of the sky, Orion, the Hunter of ancient Greece. He crosses high to the south during northern winter. Straddling the celestial equator, his bold seven-star pattern dominates the starry night. In one story, he was killed by Diana, who was fooled by jealous Apollo into thinking he was a deer. In another, he was done in by Scorpius, the Zodiac's scorpion, the gods then placing him in the heavens opposite his nemesis.

At the upper left of Orion glows the magnificent red supergiant Betelgeuse, a dying star some four times the size of Earth's orbit, while at the lower right is the blue supergiant Rigel. The names derive from corruptions of ancient Arabic, respectively meaning the hand and foot of the "Central One," a mysterious woman. Between them is his most prominent feature, three bright stars in a row that make his Belt. To the Arabs they were a string of pearls." To the upper right of the Belt lies Bellatrix, to the lower left Saiph. Both are blue-white in color. All seven are massive enough to collapse internally and explode.

But don't worry, as they are hundreds of light years away (a light year the distance light travels in a year at 186,000 miles per second), too far for this most catastrophic of stellar events to disturb us. Unlike most constellations, much of Orion is made of stars related by birth a few million years ago. You can see some of the birth process going on today. With binoculars, look down from the Belt to the vertical three-star Sword. In the middle is a glowing patch, the Orion Nebula ("nebula" Latin for "cloud"), a vast remnant of the latest round of star formation. Some 20 light years across, it's lit up by the ultraviolet light from a complex set of hot massive stars called the "Trapezium" and is among the great telescopic sights of the nighttime sky.

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Copyright © James B. Kaler, all rights reserved. These contents are the property of the author and may not be reproduced in whole or in part without the author's consent except in fair use for educational purposes. First published in the October-December 2015 Clark-Lindsey Village Voice.