Aries is a small, faint patch of sky that carries a huge reputation. It is the first sign of the zodiac, and the reason is a matter of timing: about 2,000 years ago, when the Greeks and Babylonians were drawing up the calendar of the heavens, the sun stood in Aries at the spring equinox. The year began there, so the zodiac began there too.
The ram of the myth
In Greek myth the ram is the one with the golden fleece. A cloud goddess, Nephele, sent a flying ram to rescue her two children, Phrixus and Helle, from a plot by their stepmother. Helle lost her grip and fell into the narrow sea that was then called the Hellespont, which is named after her. Phrixus reached the kingdom of Colchis on the Black Sea, sacrificed the ram to Zeus, and hung the fleece in a sacred grove guarded by a sleepless dragon. Years later Jason and the Argonauts sailed to fetch it. Zeus set the ram among the stars as a reward.
Why the first sign is not the first sign any more
The earth's axis wobbles slowly, like a spinning top, and the wobble moves the equinox backward through the constellations at about one degree every 72 years. This is called precession, and the Greek astronomer Hipparchus is credited with discovering it in the second century BCE. By now the spring equinox has drifted out of Aries and into Pisces. Astrologers get around this by using the signs as twelve equal slices of the year, tied to the seasons instead of the stars, while astronomers still call the equinox point the First Point of Aries.
The sign and its symbol
The Aries glyph is usually read as the horns and brow of a ram, though it also looks like a sprouting seedling, which suits a sign tied to spring. Traditional astrology ties Aries to Mars. The constellation's brightest star, Hamal, takes its name from the Arabic word for a lamb.
How to find it
To find Aries, look for a short, crooked line of three modest stars, Hamal, Sheratan and Mesarthim, between the bright Pleiades and the Great Square of Pegasus. In the northern hemisphere it is highest on autumn and early winter evenings. There is no spectacular sight to look for, which makes the first sign of the zodiac a good test of a dark sky.
On the star chart
In Sidney Hall's 1824 star-chart card, the ram lies with its head turned and its gilded horns curled, and a small fly, Musca Borealis, hovers above its back. That fly was a constellation invented by astronomers in the 1600s and 1700s and has since been dropped from the official list, so the card preserves a vanished piece of the sky.
Little-known facts
- Hamal is an orange giant about 66 light years away.
- Aries was one of the 48 constellations listed by Ptolemy in the second century.
- The Babylonians knew the same stars as the Hired Man, a farm laborer, before the Greeks pictured a ram.
Aries appears on our:
