Alnilam: how to find it and when to see it
Alnilam ranks 29th of the 74 bright stars on our list, at magnitude 1.69, in the constellation Orion.
You can see it from anywhere south of 89° N, and it's highest in the evening sky in January.
Alnilam at a glance
- Constellation
- Orion
- Magnitude
- 1.69
- Rank on our list
- 29 of 74
- Hemisphere
- Southern
- Right ascension
- 5 h 36 min
- Declination
- 1.2° south
- Visible from
- south of 89° N
- Never sets
- south of 89° S
- Best evening
- January 29
- Name from
- Arabic
Where Alnilam is in the sky
Alnilam sits 1.2° 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 5 h 36 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 Alnilam
From the northern hemisphere
From 40° N, the latitude of New York, Madrid and Beijing, Alnilam rises in the east, climbs to 49° above the horizon in the south and sets in the west.
It's in the evening sky from November to April, and it's highest in the evening around January 29, in winter.
From the southern hemisphere
From 34° S, the latitude of Sydney, Cape Town and Buenos Aires, Alnilam rises in the east, climbs to 57° above the horizon in the north and sets in the west.
It's in the evening sky from November to April, and it's highest in the evening around January 29, in summer.
How high Alnilam 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 | Rises and sets | 29° in the south | Dec to Mar |
| 50° N | Rises and sets | 39° in the south | Dec to Mar |
| 40° N | Rises and sets | 49° in the south | Nov to Apr |
| 30° N | Rises and sets | 59° in the south | Nov to Apr |
| 20° N | Rises and sets | 69° in the south | Nov to Apr |
| Equator | Rises and sets | 89° in the south | Nov to Apr |
| 20° S | Rises and sets | 71° in the north | Nov to Apr |
| 34° S | Rises and sets | 57° in the north | Nov to Apr |
| 45° S | Rises and sets | 46° in the north | Nov to Apr |
What the name Alnilam means
Alnilam comes from the Arabic al-niẓām, the string of pearls. It's the middle star of Orion's Belt.
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 Alnilam was above the horizon that night, it's on your map, and we print it on museum-grade paper.
Questions about Alnilam
Alnilam is in Orion. It sits 1.2° south of the celestial equator, at a right ascension of 5 h 36 min.
Alnilam is highest in the evening sky around January 29. That's winter in the northern hemisphere and summer in the southern hemisphere.
Yes, from anywhere south of 89° N. From 40° N, it climbs to 49° above the horizon in the south.
Alnilam has a magnitude of 1.69, which ranks it 29th of the 74 bright stars on our list. Sirius looks about 18 times brighter.
Alnilam comes from the Arabic al-niẓām, the string of pearls. It's the middle star of Orion's Belt.