Gamma Coronae Borealis — Double Star in Corona Borealis
Observe
1Physical Properties
Magnitude
3.84
Range
3.81 - 3.82
Period
21.4 hours
Variable Type
Ellipsoidal Variable
Spectral Type
A0V
Star Color
Blue-white
(B-V 0.00)
Distance
146 ly
2Position & Identifiers
RA
15h 42m 44.6s
Dec
+26° 17' 44.0"
Constellation
Corona Borealis
(CrB)
HR
5849
HIP
76952
HD
140436
SAO
83958
Bayer
Gamma
Flamsteed
8 CrB
Variable ID
Gam CrB
Double Cat
9757
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Medium+ | Medium+ |
| 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
Apr – Jun
(peak: May)
5Light Curve
6Multiple Star System
Separation
0.2″
Companion Mag
5.6
Companion Sp
A3V
Position Angle
121°
Star Colors
A: Blue-white
B: White
Discoverer
STF1967
4.08 A0IV, 5.51 A3V, 91.0y, a = 0.74". Combined mag., color.
Separation over time
Period: 10.1 y
Eccentricity: 0.478
Now: 0.20", PA 271°
+ 0.49" in 5 years
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
Explore
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
Discover
16Stellar Notes
Delta Sct 3.80-3.86V, 0.030d. Mass 1.9 solar. Possibly beat period?
ADS 9757A.
Hyades group.
0.018".
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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