Observe
1Physical Properties
Magnitude
5.95
Range
5.33 - 6.94
Period
242 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M6IIIase
Star Color
Red
(B-V 1.67)
2Position & Identifiers
RA
09h 10m 38.7s
Dec
+30° 57' 47.0"
Constellation
Cancer
(Cnc)
HR
3639
HIP
45058
HD
78712
Variable ID
RS Cnc
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.3 – 6.9 mag
Amplitude
1.6 mag
Period
242.2 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | Imp. |
| 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
Jan – Mar
(peak: Feb)
5Light Curve
6Comparison Stars for RS Cnc (5.3–6.9)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
7
Size Comparison
Querying VizieR for stellar data…
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
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11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
SRc? 6.2 - 7.7p, 120d. Mean mag. varies in period 1700d.
Technetium star. CO emission. OH radio emission.
Survey Image
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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
Cancer
Mythology, bright stars, and deep-sky highlights.
Constellation
