Sigma Arae — Star in Ara
Observe
1Physical Properties
Magnitude
4.59
Spectral Type
A0V
Star Color
Blue-white
(B-V -0.03)
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | Hard+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
Best season
May – Jul
(peak: Jun)
5Survey Image
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Explore
6
Size Comparison
Querying VizieR for stellar data…
7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
NGC 6388
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 6.9
1.8°
Scorpius
Sargas
HIP 86228; Theta Scorpii
Easy double, sep 6.5″
Double Star
mag 1.87
3.5°
Scorpius
IC 4651
Rich open cluster
Open Cluster
mag 6.9
3.9°
Ara
V539 Ara
Eclipsing binary, period 3.2d
Variable Star
mag 5.92
7.5°
Ara
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Article
Ara
Mythology, bright stars, and deep-sky highlights.
Constellation
