Rho Cassiopeiae — Star in Cassiopeia
Observe
1Physical Properties
Magnitude
4.54
Range
4.1 - 6.2
Variable Type
Yellow Hypergiant
Spectral Type
G20e
Star Color
Yellow
(B-V 1.22)
(reddened by dust)
Distance
142 ly
2Position & Identifiers
RA
23h 54m 23.0s
Dec
+57° 29' 58.0"
Constellation
Cassiopeia
(Cas)
HR
9045
HIP
117863
HD
224014
SAO
35879
Bayer
Rho
Flamsteed
7 Cas
Variable ID
Rho Cas
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | Medium |
| 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
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7
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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
SRd 4.1 - 6.2v, periods about 110 and 1100d (1946 minimum lasted 320d). Rapid spectral variation from cF5 to M5p. | Photoelectric observations since June 1986 indicate an amp. of only about 0.8V and 0.3(B-V).
Possibly wide CPM pair with HR 9052.
Cas OB5, within 51' of center of cluster NGC 7789, nonmember.
Also classified F8Ia-K0pIa-0.
Envelope has expansion velocity about 40k/s.
15
Light Travel Time Machine
16
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.
V373 Cas
Variable star, range 5.9–6.3
Variable Star
mag 6.00
0.2°
Cassiopeia
Caroline's Rose
NGC 7789
Rich open cluster
Open Cluster
mag 6.7
0.9°
Cassiopeia
V640 Cas
Tight double — a rewarding split at 1.5″
Double Star
mag 5.96
1.8°
Cassiopeia
Chaph
HIP 746; Beta Cassiopeiae; 11 Cassiopeiae
Bright naked-eye star, mag 2.3
Star
mag 2.27
2.5°
Cassiopeia
IC 10
Galaxy
Galaxy
mag 10.3
3.8°
Cassiopeia
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