48 Persei — Star in Perseus
Observe
1Physical Properties
Magnitude
4.04
Range
3.97 - 4.06
Period
72 days
Variable Type
Gamma Cassiopeiae (Eruptive Be Star)
Spectral Type
B3Ve
Star Color
Blue
(B-V -0.03)
Distance
163 ly
2Position & Identifiers
RA
04h 08m 39.7s
Dec
+47° 42' 45.0"
Constellation
Perseus
(Per)
HR
1273
HIP
19343
HD
25940
SAO
39336
Flamsteed
48 Per
Variable ID
MX 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
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
5Survey Image
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Explore
7
Size Comparison
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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
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15Stellar Notes
Gamma Cas 4.00 - 4.10V, 55?d. Slow var. possibly associated with emission spectrum.
16.934615d not confirmed.
Per OB3; member of Pleiades group.
Excess IR emission.
Pole on.
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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The Hertzsprung-Russell Diagram — Reading Stars Like a Map
The HR diagram turns the night sky into a physics map: every named star has a spot, every spot tells you mass, age, and fate. A guide for amateur observers.
Article
Perseus
Mythology, bright stars, and deep-sky highlights.
Constellation
