AO Cassiopeiae — Star in Cassiopeia
Observe
1Physical Properties
Magnitude
6.14
Range
6.07 - 6.24
Period
3.5 days
Variable Type
Ellipsoidal Variable
Spectral Type
O9IIInn
bright giant
Star Color
Blue-white
(B-V -0.13)
2Position & Identifiers
RA
00h 17m 43.0s
Dec
+51° 25' 59.0"
Constellation
Cassiopeia
(Cas)
HR
65
HIP
1415
HD
1337
SAO
21273
Variable ID
AO Cas
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard | Hard | V. hard+ |
| 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
Aug – Oct
(peak: Sep)
5Survey Image
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Explore
6
Size Comparison
Querying VizieR for stellar data…
7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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14Stellar Notes
EB 5.96 - 6.11B, 6.07 - 6.24V, O9III+O9III, 3.523487d. Spontaneous var. in period. Polarization indicates | circumstellar envelope possibly related to mass exchange.
3.5236d, K 223.4k/s, V0 -31.1k/s, msin3i 10.1, asini 10.8. Apsidal period about 70y? vsini of secondary 145k/s.
In neutral hydrogen region.
Also classified O9IIIn, O9.5III, O8, and O9.5I. There are also indications of two O9III components.
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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