Say hello to Aries the Ram

Sky chart showing the constellation Aries.
The constellation Aries the Ram with its brightest star, Hamal.
Antique etching of ram with star chart superimposed.
The constellation Aries the Ram. His head is turned backward, looking in the direction of the Pleaides star cluster. Image via Sidney Hall/ Urania’s mirror/ Wikimedia Commons.

Aries the Ram ranks 11th smallest out of the 12 zodiac constellations. December is a great month to spot it, and if you do, consider yourself one of the special few who have tracked it down. Aries has few bright stars, yet there is still much to see here. It’s home to the Northern Fly asterism, and the planet Uranus is currently taking up residence within its borders.

Star chart with stars in black on white of constellation Aries also showing ecliptic.
Sky chart of the constellation Aries the Ram, showing the Pleiades star cluster near the Pisces/Taurus border. Image via Wikimedia Commons.

How to see Aries the Ram

The best time to behold the Mighty Ram is when the Earth is on the other side of the sun from the constellation. November and December are especially good months for viewing Aries the Ram in all his starlit majesty. During those months, this constellation shines above the eastern horizon at nightfall and stays out for most of the night. Aries culminates – reaches its highest point in the sky – at about 10 p.m. your local time in late November, 8 p.m. your local time in late December and 6 p.m. your local time in late January.

Aries is not a particularly prominent constellation, so a dark country sky absent of moonlight is most desirable for viewing the Ram at its finest. The three stars depicting the Ram’s bust – Hamal, Sheratan and Mesartim – suddenly brighten in a dark sky, as if someone had turned up the dimmer switch. By the way, a small telescope reveals that Mesartim is a double star.

Fortunately, the head of the Ram is fairly easy to locate. You’ll find it midway between these two signposts: the Pleiades star cluster to the east and the Great Square of Pegasus to the west. The Ram’s head is actually turned backward, as if admiring the Pleiades – or perhaps his own golden fleece.

Or use Cassiopeia to find the Ram

You can also star-hop to Aries by drawing an imaginary line from Polaris, the North Star, and through a certain star in the constellation Cassiopeia: Segin (Epsilon Cassiopeiae). You’re seeking the star at the east end of the famed starlit W or M, as shown on the sky chart below. It’s a very long hop, more than twice the Polaris/Segin distance. Jump until you land between the Pleiades cluster and the Great Square of Pegasus.

Star chart of the constellation Cassiopeia.
Look for Cassiopeia high over Polaris, the North Star, around 8 p.m. your local time in early December and 6 p.m. in early January. Then use Cassiopeia to star-hop to Aries by drawing an imaginary line from Polaris, the North Star, and through the star Segin (Epsilon Cassiopeiae).
If you’re not sure how to find the North Star with respect to Cassiopeia in December and January, this chart should help.

What is the First Point of Aries?

The First Point of Aries marks the sun’s position in front of the constellations of the zodiac on the Northern Hemisphere’s spring equinox or Southern Hemisphere’s autumnal equinox. This equinox happens yearly on or near March 20, as the sun crosses the celestial equator, going from south to north.

The First Point of Aries, which is actually in the constellation Pisces nowadays, defines the coordinate system on the celestial sphere. The First Point of Aries always coincides with 0o right ascension and 0o declination. Right ascension is the equivalent of longitude here on Earth. Declination on the sky’s dome is the equivalent of latitude.

The First Point of Aries is one of two places on the celestial sphere where the ecliptic and celestial equator intersect. The First Point of Libra resides 180 degrees east of the First Point of Aries, marking the September equinox point on the celestial sphere.

Celestial sphere with latitude and longitude lines and position of Aries.
By definition, the sun resides at the First Point of Aries on the March equinox. This point has a declination of zero degrees and a right ascension of zero degrees. The ecliptic and celestial equator intersect on the March and September equinoxes, and the celestial equator is equal to a declination of 0o. Image via Wikimedia Commons.

Why is the First Point in Pisces?

Because the Earth’s rotational axis wobbles full circle relative to the backdrop stars in about 26,000 years, Polaris doesn’t remain the North Star forever, and the equinox points don’t remain fixed relative to the stars of the zodiac. The March equinox point drifts westward (along the ecliptic) through the constellations of the zodiac at about one degree (two sun diameters) in 72 years, or 30 degrees in 2,160 years.

Hence, the March equinox point passed out of the constellation Aries and into the constellation Pisces in 68 B.C. Even so, we still call this equinox point the First Point of Aries.

Hamal, brightest star in Aries

Hamal, or Alpha Arietis, is the brightest star in Aries. This orange giant star shines at magnitude 2 and lies a bit more than 65 light-years from Earth.

Hamal means head of the ram, a fitting name. Sailors once used Hamal to help in navigation. The star is the 50th brightest in the sky.

The celestial Ram in star lore

In Greek mythology, Aries represents the supernatural Ram that was sent by Zeus to rescue the children of Athamus, the King of Thebes, from political intrigue. Phrixus and his sister Helle were about to meet their demise, but the flying Ram, which could both speak and reason, took them away in the nick of time.

The children held on tight as the Ram flew them away for the safety of Colchis, an ancient kingdom bordering the eastern shore of the Black Sea. Unfortunately, Helle fell into the sea and drowned before reaching their destination. Hellespont – the ancient name for the Dardanelles Strait near Istanbul, Turkey – marks the place of her death, named in her honor.

Phrixus survived the long trip to Colchis. He gave thanks by sacrificing the Ram to Zeus, hanging it in a sacred grove where the fleece turned to gold. Later on, Jason and the Argonauts recovered the Golden Fleece.

Map with three countries in green, red, and yellow.
View larger. | Map showing the ancient Kingdom of Colchis on the eastern shore of the Black Sea. Image via Wikimedia Commons.

Bottom line: How to see the constellation Aries the Ram, plus info about this constellation in the history of astronomy and mythology.

All 12 (13) zodiac constellations

Taurus? Here’s your constellation
Gemini? Here’s your constellation
Cancer? Here’s your constellation
Leo? Here’s your constellation
Virgo? Here’s your constellation
Libra? Here’s your constellation
Scorpius? Here’s your contellation
Sagittarius? Here’s your constellation
Capricornus? Here’s your constellation
Aquarius? Here’s your constellation
Pisces? Here’s your constellation
Aries? Here’s your constellation
Birthday late November to early December? Here’s your constellation

December 9, 2021

Like what you read?
Subscribe and receive daily news delivered to your inbox.

Your email address will only be used for EarthSky content. Privacy Policy
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

More from 

Bruce McClure

View All