Observe
1Physical Properties
Magnitude
4.72
Range
4.70 - 4.74
Period
2.1 hours
Variable Type
BCEP:
Spectral Type
B2IV
subgiant
Star Color
Blue-white
(B-V -0.08)
2Position & Identifiers
RA
12h 04m 19.2s
Dec
-63° 09' 56.0"
Constellation
Crux
(Cru)
HR
4603
HIP
58867
HD
104841
SAO
251717
Bayer
Theta2
Variable ID
The2 Cru
Querying VizieR catalog...
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
Feb – Apr
(peak: Mar)
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
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14Stellar Notes
Beta C 4.70 - 4.74V, 0.0889d. See HR 4573.
3.4280d, K 51.3k/s, V0 +16.1k/s, asini 2.42.
Sco-Cen assoc.; doubtful member of the Sco-Cen cluster.
Also classified B3IV.
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 4052
Open cluster
Open Cluster
mag 9.0
0.3°
Crux
Alpha Cru
HIP 60718; Alpha2 Crucis
Hot blue O-type star
Star
mag 1.73
2.5°
Crux
Lambda Centauri Nebula
IC 2944
Emission nebula — try an OIII filter
Emission Nebula
mag 4.5
3.2°
Centaurus
Coalsack Nebula
Dark nebula — shows as a void against the Milky Way
Dark Nebula
mag 12.0
4.9°
Crux
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Article
Crux
Mythology, bright stars, and deep-sky highlights.
Constellation
