COSMOS / CONSTELLATIONS / MON
Monoceros (Unicorn)
The Unicorn. IAU abbreviation Mon.
STAR CHART
KEY FACTS
- IAU abbreviation
- Mon
- Latin name / genitive
- Monoceros / Monocerotis
- Position
- Right ascension ≈ 6 h 51 m; declination −11° to +12°
- Visibility from Türkiye
- Visible in full from anywhere in Türkiye. When it crosses the meridian its centre stands about 50° above the horizon from Ankara.
- Best time to observe
- Best placed at 21:00 Türkiye time around 2 March.
- Number of stars
- 142 stars brighter than magnitude 6.5 in the catalogue; 15 brighter than 5 and 3 brighter than 4.
INTERACTIVE LAB
Where is Monoceros tonight?
The lab opens for Ankara on today’s date. Drag the time slider through the night; the “Best night” button jumps to the date when the constellation is highest at 21:00 (around 2 March). Change the city to compare the view from elsewhere in Türkiye and around the world.
MYTH, HISTORY AND OBSERVING
Introduced by Plancius in 1613, it lies in the winter Milky Way east of Orion. It has no bright stars but is rich in deep-sky objects: the Rosette Nebula, the Christmas Tree Cluster (NGC 2264) and the open cluster M50. Beta Monocerotis is a fine triple star in a small telescope.
BRIGHTEST STARS
| Star | Magnitude | Distance (light-years) | Spectral type |
|---|---|---|---|
| β Mon | 3.76 | 677 | B3Ve |
| α Mon | 3.94 | 148 | K0III |
| γ Mon | 3.99 | 498 | K3III |
| δ Mon | 4.15 | 384 | A2V |
| ζ Mon | 4.36 | 1,059 | G2Ib |
| ε Mon | 4.39 | 122 | A5IV |
| 13 Mon | 4.47 | — | A0Ib |
| 18 Mon | 4.48 | 368 | K0III |
Magnitude: apparent brightness; the smaller the number, the brighter the star. Distances derive from parallax measurements and are uncertain for distant stars. Source: HYG v4.1 star catalogue (CC BY-SA 4.0).
SOURCES
Position, visibility and best observing time were computed approximately for this page from the catalogue stars (Ankara, 39.9° N). The 88 constellations were adopted by the IAU in 1922; their boundaries were drawn by Eugène Delporte in 1930.