COSMOS / CONSTELLATIONS / SEX
Sextans (Sextant)
The Sextant. IAU abbreviation Sex. One of the seven constellations introduced by Johannes Hevelius and published in his star atlas of 1690.
STAR CHART
KEY FACTS
- IAU abbreviation
- Sex
- Latin name / genitive
- Sextans / Sextantis
- Position
- Right ascension ≈ 10 h 16 m; declination −11° to +6°
- Visibility from Türkiye
- Visible in full from anywhere in Türkiye. When it crosses the meridian its centre stands about 47° above the horizon from Ankara.
- Best time to observe
- Best placed at 21:00 Türkiye time around 23 April.
- Number of stars
- 40 stars brighter than magnitude 6.5 in the catalogue; 1 brighter than 5 and 0 brighter than 4.
INTERACTIVE LAB
Where is Sextans 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 23 April). Change the city to compare the view from elsewhere in Türkiye and around the world.
MYTH, HISTORY AND OBSERVING
A faint constellation that Hevelius introduced in memory of the astronomical sextant he lost when fire destroyed his house and observatory in 1679. It lies south of Regulus; its brightest star is only magnitude 4.5.
BRIGHTEST STARS
| Star | Magnitude | Distance (light-years) | Spectral type |
|---|---|---|---|
| α Sex | 4.48 | 283 | A0III |
| γ Sex | 5.07 | 278 | A2V |
| β Sex | 5.08 | 405 | B6V |
| δ Sex | 5.19 | 322 | B9.5V |
| ε Sex | 5.25 | 193 | F2III |
| HIP 51046 | 5.60 | 397 | M0.5III |
| 18 Sex | 5.64 | 473 | K2III |
| HIP 47960 | 5.65 | 263 | F4IV |
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.