the little horse · pronounced eh-KWOO-lee-us. Equuleus is the second-smallest IAU constellation, larger only than Crux, and represents a foal or little horse beside Pegasus. Ptolemy listed it among the classical 48, although its mythology is less consistent than the brighter neighboring figures: accounts associate it with Celeris, brother of Pegasus, or with the horse revealed when Neptune struck the earth. The constellation contains no star brighter than fourth magnitude, so it is best found by starting at Enif in Pegasus and Delphinus’s compact diamond. Its small quadrilateral is highest on Northern Hemisphere autumn evenings and remains visible from most inhabited latitudes. Kitalpha, the brightest star, has a traditional name meaning “part of the horse.” Equuleus lacks showpiece Messier objects, but close double stars such as Epsilon Equulei and faint galaxies reward patient telescopic observation. The official IAU boundary is a precise patch of sky, whereas the ancient foal is an interpretive line figure. Its proximity to Pegasus creates an obvious thematic relationship, but the two remain separate official constellations rather than duplicate entries or subdivisions of one modern region.
About Equuleus
Equuleus is one of the 88 constellations recognized by the International Astronomical Union. Its standard three-letter abbreviation is Equ, and astronomers use the genitive form Equulei when naming stars associated with it. The constellation's reference position lies around right ascension -2.6 hours and declination +12 degrees.
Its location places it in the celestial equator. For a typical mid-latitude observer, this part of the celestial sphere is especially well placed during summer evenings. Exact visibility depends on latitude, local horizon, date and time.
History and mythology of Equuleus
Historical origin
The constellation contains no star brighter than fourth magnitude, so it is best found by starting at Enif in Pegasus and Delphinus’s compact diamond. Its small quadrilateral is highest on Northern Hemisphere autumn evenings and remains visible from most inhabited latitudes.
The modern constellation
Equuleus became one of the 88 official constellations standardized by the International Astronomical Union. Its boundary is a coordinate-defined sky region, while the familiar line figure joins only selected stars and has no physical depth.
Reading the cultural record
Names and stories attached to this part of the sky changed across languages, periods and communities. Cultural parallels should be identified from specialist sources rather than presented as interchangeable versions of Equuleus.
How to find Equuleus
- Use a location-aware chart and observe when Equuleus reaches its highest evening altitude; check that the full constellation rises from your latitude.
- Locate Kitalpha, magnitude 3.9, then compare its direction with a brighter neighboring constellation rather than relying on line art alone.
- Trace the main pattern toward Delta Equulei; binoculars reveal the fainter connecting stars while preserving a wide field.
- Move to NGC 7046 with a low-power eyepiece or binoculars, then increase magnification only if its surface brightness permits.
Bright stars in Equuleus
Kitalpha
Notable star- Magnitude
- 3.9
- Distance
- 190 ly
A spectroscopic binary whose traditional name refers to a portion of the little horse.
Delta Equulei
Notable star- Magnitude
- 4.5 combined
- Distance
- 60 ly
A short-period visual binary whose orbit has been measured in detail.
Gamma Equulei
Notable star- Magnitude
- variable about 4.7
- Distance
- 118 ly
A chemically peculiar, rapidly oscillating Ap star with a strong magnetic field.
Deep-sky objects in Equuleus
NGC 7046
A faint barred spiral and one of the constellation’s more approachable galaxy targets.
NGC 7015
A small galaxy requiring a dark sky and moderate aperture.
NGC 7040
A dim extragalactic target in the compact Equuleus field.
Interesting facts about Equuleus
- Equuleus’s traditional name refers to little horse, while its official IAU boundary defines a precise region of the sky.
- Kitalpha, at magnitude 3.9, is a key star in Equuleus. A spectroscopic binary whose traditional name refers to a portion of the little horse.
- NGC 7046 is a notable barred spiral galaxy in Equuleus. A faint barred spiral and one of the constellation’s more approachable galaxy targets.
- NGC 7015, a spiral galaxy, is another observing target within the constellation.
- The constellation contains no star brighter than fourth magnitude, so it is best found by starting at Enif in Pegasus and Delphinus’s compact diamond.