1 Persei — Variable Star in Perseus
Excellent (60/100)
Observe
1Physical Properties
Magnitude
5.52
Range
5.49 - 5.85
Period
25.9 days
Variable Type
Eclipsing Binary (Algol-type)
Spectral Type
B1.5V
Star Color
Blue
(B-V -0.18)
2Position & Identifiers
RA
01h 51m 59.3s
Dec
+55° 08' 51.0"
Constellation
Perseus
(Per)
HR
533
HIP
8704
HD
11241
SAO
22690
Flamsteed
1 Per
Variable ID
V436 Per
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.5 – 5.9 mag
Amplitude
0.4 mag
Period
25.94 d
Type
EA/D
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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)
5Survey Image
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6Light Curve
7Comparison Stars for 1 Per (5.5–5.8)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
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16Stellar Notes
E? 5.46 - 5.68y.
15.6d, K 10k/s, V0 -9k/s.
In neutral hydrogen region; Cas-Tau OB1.
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
Perseus
Mythology, bright stars, and deep-sky highlights.
Constellation
