Ram · pronounced Aries. Aries, meaning “Ram,” is an official IAU constellation centred near right ascension 2.8 hours and declination 22°. Its observing character is defined by the named stars and targets below. Aries inherited the ram from Mesopotamian and Greek traditions; Greek myth linked it with the golden-fleeced ram that rescued Phrixus and Helle. The March equinox lay here in antiquity, but precession has shifted that point into Pisces. The line figure is only a guide: the IAU boundary is the scientifically meaningful region, while historical and cultural interpretations require their own context.
About Aries
Aries is one of the 88 constellations recognized by the International Astronomical Union. Its standard three-letter abbreviation is Ari, and astronomers use the genitive form Arietis when naming stars associated with it. The constellation's reference position lies around right ascension 2.8 hours and declination +22 degrees.
Its location places it in the northern sky. For a typical mid-latitude observer, this part of the celestial sphere is especially well placed during autumn evenings. Exact visibility depends on latitude, local horizon, date and time.
History and mythology of Aries
Origins and cultural history
Aries inherited the ram from Mesopotamian and Greek traditions; Greek myth linked it with the golden-fleeced ram that rescued Phrixus and Helle. The March equinox lay here in antiquity, but precession has shifted that point into Pisces.
From figure to official region
The IAU retained Ram as one of 88 official constellations in 1922; Eugène Delporte’s boundaries later turned the traditional figure into an exact cataloguing region.
How to find Aries
- Locate the Pleiades in Taurus and the Great Square of Pegasus.
- Look between them for Hamal and Sheratan, Aries’s conspicuous pair.
- Use a telescope on nearby Mesarthim to split its balanced white components.
- Aries is best in October–December evenings from both hemispheres.
Bright stars in Aries
Hamal (Alpha Arietis)
Notable star- Magnitude
- 2.00
- Distance
- about 66 light-years
Orange giant and brightest star in Aries.
Sheratan (Beta Arietis)
Notable star- Magnitude
- 2.64
- Distance
- about 60 light-years
White spectroscopic binary near Hamal.
Mesarthim (Gamma Arietis)
Notable star- Magnitude
- 3.86 combined
- Distance
- about 164 light-years
Fine, nearly equal double star for small telescopes.
Botein (Delta Arietis)
Notable star- Magnitude
- 4.35
- Distance
- about 170 light-years
Orange giant marking the eastern part of the figure.
Deep-sky objects in Aries
NGC 772
Asymmetric galaxy with one elongated arm, probably distorted by companion NGC 770.
NGC 1156
Isolated star-forming dwarf with a mottled visual appearance.
NGC 972
Dusty starburst galaxy seen at an oblique angle.
NGC 678 and NGC 680
Contrasting edge-on spiral and elliptical galaxy in the same field.
Meteor showers associated with Aries
Daytime Arietids
Peak: around 7 JuneStrong radio meteor shower whose radiant is near the Sun; only a few meteors appear near dawn.
Interesting facts about Aries
- Aries’s traditional name refers to ram, while its official IAU boundary defines a precise region of the sky.
- Hamal (Alpha Arietis), at magnitude 2.00, is a key star in Aries. Orange giant and brightest star in Aries.
- NGC 772 is a notable spiral galaxy in Aries. Asymmetric galaxy with one elongated arm, probably distorted by companion NGC 770.
- The Daytime Arietids meteor shower peaks around 7 June. Strong radio meteor shower whose radiant is near the Sun; only a few meteors appear near dawn.
- Aries inherited the ram from Mesopotamian and Greek traditions; Greek myth linked it with the golden-fleeced ram that rescued Phrixus and Helle.
Aries lies on the astronomical path of the Sun through the IAU sky regions. The Sun crosses 13 official constellations, including Ophiuchus; this is different from the equal 12-sign structure used by Western tropical astrology.