27 Cancri — Variable Star in Cancer
Good (57/100)
Observe
1Physical Properties
Magnitude
5.50
Range
5.41 - 5.75
Period
40 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M3III
giant
Star Color
Red
(B-V 1.60)
Distance
109 ly
2Position & Identifiers
RA
08h 26m 43.9s
Dec
+12° 39' 16.0"
Constellation
Cancer
(Cnc)
HR
3319
HIP
41400
HD
71250
SAO
97819
Flamsteed
27 Cnc
Variable ID
BP Cnc
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.4 – 5.8 mag
Amplitude
0.3 mag
Period
40 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard+ | V. hard |
| 50 mm finder 50mm finder | Hard+ | Hard+ | Hard+ |
| 150 mm telescope 150mm scope | Hard+ | Hard+ | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Out of reach for typical amateur telescopes, even at Bortle 3.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Dec – Feb
(peak: Jan)
5Survey Image
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6Light Curve
7Comparison Stars for 27 Cnc (5.4–5.8)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
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 5.41 - 5.75V, about 40d.
Arcturus group.
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.
R Cnc
Mira-type variable, range 6.2–11.8
Variable Star
mag 7.13
2.7°
Cancer
M67
King Cobra or Golden Eye Cluster
Open cluster
Open Cluster
mag 6.1
6.1°
Cancer
NGC 2513
Elliptical galaxy
Galaxy
mag 13.0
6.8°
Cancer
X Cnc
Semi-regular variable, range 5.6–7.5
Variable Star
mag 6.64
8.3°
Cancer
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