Phi Persei — Star in Perseus
Observe
1Physical Properties
Magnitude
4.07
Range
3.96 - 4.15
Period
19.5 days
Variable Type
Gamma Cassiopeiae (Eruptive Be Star)
Spectral Type
B2Vep
Star Color
Blue
(B-V -0.04)
Distance
130 ly
2Position & Identifiers
RA
01h 43m 39.6s
Dec
+50° 41' 19.0"
Constellation
Perseus
(Per)
HR
496
HIP
8068
HD
10516
SAO
22554
Bayer
Phi
Variable ID
Phi Per
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | 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
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Best season
Sep – Nov
(peak: Oct)
5Survey Image
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Explore
7
Size Comparison
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8
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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
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15Stellar Notes
Gamma Cas 4.03 - 4.11V, 19.5d. Amp. varies in per. 127d. Possible mass loss. Expanding circumstellar shell.
126.696d. Primary, 16.8k/s, V0 -8.4k/s, msin3i 21.1, asini 29.2; secondary K 105.3k/s, sin3i 3.4, | asini 184. Unresolved by speckle interferometry. Both components appear to be shell stars, B2Ve and B3Ve. Speculation | that secondary is the helium core of a once more massive star whose mass was transferred to the primary.
In neutral hydrogen region; Cas-Tau OB1.
FeII, H in emission. Also classified B0nne, B1III-Vpe.
16
Light Travel Time Machine
17
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.
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