digital document

A Field Book of the Stars/Ursa Major

From Wikisource
Jump to navigation Jump to search

URSA MAJOR (er'sa mā'-jor)—THE GREAT BEAR. (Face North.)

Location.—Ursa Major is probably the best known of the constellations, and in this work I presuppose that the reader is familiar with its position in the heavens. It is one of the most noted and conspicuous constellations in the northern hemisphere, and is readily and unmistakably distinguished from all others by means of a remarkable cluster of seven bright stars in the northern heavens, forming what is familiarly termed "the Dipper."

The stars (α) and (β) are called the pointers, because they always point toward Polaris, the Pole Star, 28 3/4 degrees distant from (α).

Alioth is very nearly opposite Shedir in Cassiopeia, and at an equal distance from the Pole. The same can be said of Megres, in Ursa Major, and Caph, in Cassiopeia.

The star (ο) is at the tip of the Bear's nose. A clearly defined semicircle begins at (ο) and ends in the pair (ι) and (κ) at the extremity of the Bear's right fore paw. This group of stars resembles a sickle. Note little Alcor close to Mizar. This star was used by the Arabs as a test of good eyesight. Mizar and Alcor are known as the horse and his rider.

Note also a faint star near (α) in direction of (β). This plate shows the Bear lying on his back, his feet projected up the sky; three conspicuous pairs of stars represent three of his four feet.

Ursa Major-Fieldbook of Stars-027.jpg