COSMOS / CONSTELLATIONS / PYX
Pyxis (Compass)
The Compass. IAU abbreviation Pyx. One of the 14 southern constellations that Nicolas-Louis de Lacaille introduced after observing from the Cape of Good Hope in 1751–1752.
STAR CHART
KEY FACTS
- IAU abbreviation
- Pyx
- Latin name / genitive
- Pyxis / Pyxidis
- Position
- Right ascension ≈ 8 h 49 m; declination −37° to −20°
- Visibility from Türkiye
- Visible in full from anywhere in Türkiye. When it crosses the meridian its centre stands about 22° above the horizon from Ankara.
- Best time to observe
- Best placed at 21:00 Türkiye time around 1 April.
- Number of stars
- 43 stars brighter than magnitude 6.5 in the catalogue; 8 brighter than 5 and 2 brighter than 4.
INTERACTIVE LAB
Where is Pyxis 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 1 April). Change the city to compare the view from elsewhere in Türkiye and around the world.
MYTH, HISTORY AND OBSERVING
A small constellation beside Argo, dedicated by Lacaille in 1756 to the mariner’s compass. T Pyxidis is a recurrent nova that erupts every few decades. From Türkiye it is low in the south on late-winter evenings.
BRIGHTEST STARS
| Star | Magnitude | Distance (light-years) | Spectral type |
|---|---|---|---|
| α Pyx | 3.68 | 879 | B1.5III |
| β Pyx | 3.97 | 416 | G5II/III |
| γ Pyx | 4.02 | 207 | K3III |
| κ Pyx | 4.62 | 560 | K4/K5III |
| θ Pyx | 4.71 | 503 | M0III |
| λ Pyx | 4.71 | 192 | G8III |
| ζ Pyx | 4.86 | 244 | G5III |
| δ Pyx | 4.87 | 247 | A3IV |
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.