SU Cassiopeiae — Variable Star in Cassiopeia
Excellent (60/100)
Observe
1Physical Properties
Magnitude
5.80
Range
5.70 - 6.18
Period
46.8 hours
Variable Type
Classical Cepheid (First Overtone)
Spectral Type
F5:Ib-II
Star Color
Yellow
(B-V 0.64)
Distance
326 ly
2Position & Identifiers
RA
02h 51m 58.7s
Dec
+68° 53' 19.0"
Constellation
Cassiopeia
(Cas)
HR
829
HIP
13367
HD
17463
Variable ID
SU Cas
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.8 – 6.2 mag
Amplitude
0.4 mag
Period
1.95 d
Type
DCEPS
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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
Sep – Nov
(peak: Oct)
5Light Curve
6Comparison Stars for SU Cas (5.8–6.2)
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
CDelta 5.78 - 6.16V, 1.949319d, possibly changing. RV varies in same period.
In reflection nebulosity.
16
Light Travel Time Machine
17
Relativistic Travel
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
Cassiopeia
Mythology, bright stars, and deep-sky highlights.
Constellation
