Gacrux: how to find it and when to see it
Gacrux ranks 24th of the 74 bright stars on our list, at magnitude 1.59, in the constellation Crux.
You can see it from anywhere south of 33° N, and it's highest in the evening sky in May.
Gacrux at a glance
- Constellation
- Crux
- Magnitude
- 1.59
- Rank on our list
- 24 of 74
- Hemisphere
- Southern
- Right ascension
- 12 h 31 min
- Declination
- 57.1° south
- Visible from
- south of 33° N
- Never sets
- south of 33° S
- Best evening
- May 15
- Name from
- Modern
Where Gacrux is in the sky
Gacrux sits 57.1° south of the celestial equator, the line in the sky directly above Earth's equator, so it's in the southern half of the sky. Its right ascension is 12 h 31 min.
Right ascension works like longitude on the sky. It's counted in hours, and about one hour of it turns past you each hour of the night.
When and where to see Gacrux
From the northern hemisphere
From 40° N, the latitude of New York, Madrid and Beijing, Gacrux never rises above the horizon. You need to be south of 33° N to see it.
From the southern hemisphere
From 34° S, the latitude of Sydney, Cape Town and Buenos Aires, Gacrux never sets: it circles the pole all night and climbs to 67° above the horizon in the south.
It's in the evening sky from January to September, and it's highest in the evening around May 15, in autumn.
How high Gacrux climbs from each latitude
The evening is about 9 pm local time, or 10 pm in summer time, and later when the sky is still too bright. A star counts as in the evening sky when it's at least 10° above the horizon.
| Latitude | Visibility | Highest point | Evening sky |
|---|---|---|---|
| 60° N | Never rises | Below the horizon | None |
| 50° N | Never rises | Below the horizon | None |
| 40° N | Never rises | Below the horizon | None |
| 30° N | Rises and sets | 3° in the south | None |
| 20° N | Rises and sets | 13° in the south | May |
| Equator | Rises and sets | 33° in the south | Mar to Jul |
| 20° S | Rises and sets | 53° in the south | Feb to Aug |
| 34° S | Never sets | 67° in the south | Jan to Sep |
| 45° S | Never sets | 78° in the south | All year |
What the name Gacrux means
Gacrux is a short form of Gamma Crucis, its catalogue name in Crux, the Southern Cross.
Keep the sky of a night that matters
Our star maps show the stars above any place, at the minute you choose, with the constellation lines drawn in. If Gacrux was above the horizon that night, it's on your map, and we print it on museum-grade paper.
Questions about Gacrux
Gacrux is in Crux. It sits 57.1° south of the celestial equator, at a right ascension of 12 h 31 min.
Gacrux is highest in the evening sky around May 15. That's spring in the northern hemisphere and autumn in the southern hemisphere.
Yes, from anywhere south of 33° N. From 40° N, it never rises, so you need to be further south.
Gacrux has a magnitude of 1.59, which ranks it 24th of the 74 bright stars on our list. Sirius looks about 16 times brighter.
Gacrux is a short form of Gamma Crucis, its catalogue name in Crux, the Southern Cross.