40 Comae Berenices — Variable Star in Coma Berenices
Excellent (63/100)
Observe
1Physical Properties
Magnitude
5.60
Range
5.3 - 6.1
Period
58 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M5III
giant
Star Color
Red
(B-V 1.59)
Distance
72 ly
2Position & Identifiers
RA
13h 06m 22.6s
Dec
+22° 36' 58.0"
Constellation
Coma Berenices
(Com)
HR
4949
HIP
63950
HD
113866
SAO
82651
Flamsteed
40 Com
Variable ID
FS Com
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3How easy to follow?
Magnitude
5.3 – 6.1 mag
Amplitude
0.8 mag
Period
58 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard | V. hard+ | V. hard |
| 50 mm finder 50mm finder | Medium+ | Medium | Medium |
| 150 mm telescope 150mm scope | Medium+ | Medium+ | Medium+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
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Best season
Mar – May
(peak: Apr)
5Survey Image
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6Light Curve
7Comparison Stars for 40 Com (5.3–6.1)
Nearby stable stars for estimating brightness (AAVSO)
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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
SRb 5.30 - 6.1v, 58:d.
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
Coma Berenices
Mythology, bright stars, and deep-sky highlights.
Constellation
