R Coronae Borealis — Variable Star in Corona Borealis
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Observe
1Physical Properties
Magnitude
5.85
Range
5.61 - 15.1
Period
49 days
Variable Type
R Coronae Borealis (Carbon Star)
Spectral Type
G0Iep
Star Color
Orange
(B-V 0.77)
Distance
326 ly
2Position & Identifiers
RA
15h 48m 34.4s
Dec
+28° 09' 24.0"
Constellation
Corona Borealis
(CrB)
HR
5880
HIP
77442
HD
141527
SAO
84015
Variable ID
R CrB
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.8 – 14.8 mag
Amplitude
9.0 mag
Period
48.6 d
Type
RCB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | Imp. | Imp. | Imp. |
| 150 mm telescope 150mm scope | Imp. | Imp. | Imp. |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
To reach "Medium" at Bortle 3, you'd need at least a 520 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Survey Image
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6Light Curve
7Comparison Stars for R CrB (5.8–14.8)
Nearby stable stars for estimating brightness (AAVSO)
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8
Size Comparison
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9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
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16Stellar Notes
R CB 5.8 - 14.8v. The prototype star, discovered by Pigott in 1795.
IR excess.
Hydrogen deficient carbon star. At minimum, emission of CaII, NaI, ScII, TiII, SrII, and FeII. Spectra at 2 and 10 | micrometers indicate a thick dust shell either around R CrB or a companion.
17
Light Travel Time Machine
18
Relativistic Travel
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.
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Article
Corona Borealis
Mythology, bright stars, and deep-sky highlights.
Constellation
