Tau Persei — Star in Perseus
Observe
1Physical Properties
Magnitude
3.95
Range
3.93 - 4.09
Period
1516 days
Variable Type
Eclipsing Binary (Algol-type)
Spectral Type
G4. III COMP
Star Color
Yellow
(B-V 0.74)
Distance
254 ly
2Position & Identifiers
RA
02h 54m 15.5s
Dec
+52° 45' 45.0"
Constellation
Perseus
(Per)
HR
854
HIP
13531
HD
17878
SAO
23685
Bayer
Tau
Flamsteed
18 Per
Variable ID
Tau Per
Double Cat
2202
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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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
EA, 3.94 - 4.07V.
A* 4.06 G4III+A4V, 4.150y, a = 0.050". Speckle interferometric sep. 0.080" 1981.67. Circumstellar material surrounding | the pair? Visual companions 10.7v at 51" possibly physical; 11.8v at 4" possibly optical.
ADS 2202A, 1515.6d, K 19.0k/s, V0 +2.2k/s, asini 271. vsini of secondary 50k/s.
16
Light Travel Time Machine
17
Relativistic Travel
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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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