How to Find the Aries Constellation

Northern hemisphere autumn constellations.
Northern hemisphere autumn skies, view to the south.

 Carolyn Collins Petersen

The constellation Aries, one of the oldest-known star patterns, is located right next to the constellation Taurus. Discover how to find Aries and its fascinating deep-sky objects during your next sky-gazing session.

Finding Aries

Aries is most visible in the month of November. To find Aries, look for a crooked line of three bright stars not too far from the Pleiades star cluster. The stars of Aries lie along the zodiac, the path the Sun and planets appear to follow across the sky during the year.

Aries constellation
The stars of Aries, plus a galaxy challenge. Carolyn Collins Petersen 

History of Aries

The name "Aries" is the Latin word for "ram." In the constellation Aries, two stars make up the points of a ram's horn. However, this constellation has had a wide range of different interpretations throughout history. The sky pattern was associated with a farmhand in ancient Babylon, a porpoise in the South Pacific, a pair of bureaucrats there in ancient China, and the god Amon-Ra in ancient Egypt.

Aries and Meteor Showers

Avid skywatchers know Aries from the meteor showers that bear its name and appear to radiate from the constellation at different times throughout the year, including:

  • Delta Arietids (between December 8 and January 2)
  • Autumn Arietids (between September 7 and October 27)
  • Epsilon Arietids (between October 12 and 23)
  • Daytime Arietids (between May 22 and July 2)

All of these outbursts of meteors are associated with the material left behind by comets as they make their way around the Sun. Earth's orbit intersects the comets' paths, and as a result they appear to flow from the constellation Aries. 

Aries star chart
The official IAU constellation chart for Aries. IAU/Sky Publishing 

The Stars of Aries

The three brightest stars of Aries constellation are officially called alpha, beta, and gamma Arietis. Their nicknames are Hamal, Sharatan, and Mesarthim, respectively.

Hamal is an orange giant star and lies about 66 light-years from Earth. It's about 91 times brighter than our Sun and is around 3.5 billion years old. 

Sharatan is a fairly young star, slightly more massive than the Sun and about a third brighter than our star. It lies nearly 60 light-years away from us. It also has a companion star that is much dimmer and orbits at a distance that still hasn't been determined. 

Mesarthim is also a binary star and lies about 165 light-years away from the Sun.

There other, fainter stars in Aries, too. For example, 53 Arietis is a runaway star that was violently ejected from the Orion Nebula (at the heart of the constellation Orion) in its youth. Astronomers suspect that a nearby supernova explosion sent this star on its way across space. Aries also has a few stars that are orbited by extrasolar planets. 

Deep-sky Objects in Aries

Aries contains several deep-sky objects that can be discovered through binoculars or a small telescope.

NGC 772
The spiral galaxy NGC 772 in Aries. Adam Block/Mount Lemmon Skycenter/University of Arizona. CC-BY-SA 3.0 

Perhaps the most interesting is the spiral galaxy NGC 772, which lies south of Mesarthim, and its companion galaxy, NGC 770. Astronomers refer to NGC 772 as a "peculiar" galaxy because it appears to have some structures not always seen in regular spiral galaxies. It's a star-forming galaxy and lies about 130 million light-years away. It's very likely that its interesting shape (with one very bright blue arm prominently displayed) is due to an interaction with its companion.

A few other very distant and dim galaxies are scattered throughout Aries, including NGC 821 and Segue 2, which is actually a companion galaxy to the Milky Way.