March is the month when we emerge from the winter doldrums and welcome the arrival of spring. The days lengthen at their fastest pace and the bright stars of winter retreat. Importantly, for sky watchers, the astronomical beginning of spring occurs with the vernal equinox, which falls on March 19 at 11:06 p.m. Eastern time.
At that moment, the center of the sun’s disk crosses the celestial equator into the sky’s northern hemisphere. This marked the traditional beginning of a new year in many cultures until Roman times, and today it sets the dates of important feasts and fasts in many religions.
The point in the sky that defines the equinox is sometimes referred to as the “first point of Aries,” a term still widely used in astrology. The constellation of Aries, the Ram, was the location of the equinox back in Babylonian times, when the basic tenets of astrological practice were established.
Today, the equinox actually lies some 30 degrees westward in the constellation of Pisces, the Fish, thanks to the 26,000-year cycle called “precession of the equinoxes.” In 3,000 years, the equinox will lie among the stars of Aquarius; it will return to Aries somewhere around the year 23,000.
The term “equinox” implies the concept of “equal night,” when day and night are exactly 12 hours in duration. In reality, the upper limb of the sun pokes above the horizon a few days before the equinox. The actual date for 12 hours of daylight and darkness in D.C. this year is March 16, when Old Sol rises at 7:17 a.m. Eastern time and sets at 7:17 p.m.
Moon notes, set that alarm
You’ll find the waning moon gracing the morning sky as March begins. On the morning of the 3rd, early risers can catch the last quarter moon before dawn in the southern part of the sky. Less than a degree away is the bright red-tinted star Antares, the heart of Scorpius, the Scorpion.
The new moon falls on the 10th. Luna waxes in the evening sky, reaching the full phase on the 25th. The traditional name for the March full