But Pisces is none the less a very important constellation because it is at one of the points where the line of the equator crosses the line of the ecliptic.
When the Sun crosses the point where the equator and the ecliptic meet the days and nights are then equal at all places on the Earth, and hence we call this time of the year, which is about the twenty-first of March, the equinox, which means equal days; or the vernal equinox, which means equal spring days.
Aries, the Ram.—This constellation used to be in that part of the zodiac whose sign is ♈ (Aries) but is now in that part whose sign is ♉ (Taurus).
The position of Aries in the sky is shown in [Fig. 175] and you can easily find him by drawing a line from the North Star to Alpha in Pegasus and another line at right angles to the first line until you come to two bright stars quite close together and a third one not quite so bright. These are the chief stars of the constellation of the Ram.
Taurus, the Bull.—This constellation is now in the sign ♊ (Gemini), of the zodiac. In [Chapter II] you will find directions for locating Taurus. You will remember that the red star Aldebaran forms the right eye of the Bull. The little group of stars called the Hyades is the Bull’s face and the Pleiades are in his shoulder.
Gemini, the Twins.—It is easy to see why the ancients called this constellation of the zodiac the Twins, for its two chief stars, Castor and Pollux, are quite close together and while of different colors they are of about the same brightness.
These two stars are the heads of the Twins and four other stars are their feet and these stand forever on the Milky Way. The Twins are easily found since they are next to Taurus, the Bull.