Lambda Tauri — Variable Star in Taurus
Excellent (72/100)
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1Physical Properties
Magnitude
3.47
Range
3.4 - 3.9
Period
4.0 days
Variable Type
Eclipsing Binary (Algol-type)
Spectral Type
B4IV
subgiant
Star Color
Blue-white
(B-V -0.12)
Distance
484 ly
2Position & Identifiers
RA
04h 00m 40.8s
Dec
+12° 29' 25.0"
Constellation
Taurus
(Tau)
HR
1239
HIP
18724
HD
25204
SAO
93719
Bayer
Lambda
Flamsteed
35 Tau
Variable ID
Lam Tau
Querying VizieR catalog...
3How easy to follow?
Magnitude
3.4 – 3.9 mag
Amplitude
0.5 mag
Period
3.95 d
Type
EA/DM
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard+ | Hard |
| 50 mm finder 50mm finder | Medium | Medium | Medium |
| 150 mm telescope 150mm scope | Medium | Medium | Medium |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
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Best season
Oct – Dec
(peak: Nov)
5Survey Image
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6Light Curve
7Comparison Stars for Lambda Tau (3.4–3.9)
Nearby stable stars for estimating brightness (AAVSO)
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9
Size Comparison
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10
Compare Stars
11
Spectral Classification
12
Hertzsprung-Russell Diagram
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13
Stellar Lifecycle
14
Blackbody Spectrum
15
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
16
Stellar Fusion
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17Stellar Notes
EA 3.3 - 3.80p, B3V+A, 3.952955d, i 86d.
3.9540d, K 55.4k/s, V0 +15.2k/s, asini 2.99. RV also varies in 33.025d, triple system. Masses 6.8, 1.8 and about 1 | solar.
0.0042".
18
Light Travel Time Machine
19
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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A practical guide to visual observation of variable stars: estimating magnitudes, finding comparison stars, recording data, and contributing to science with AAVSO.
Article
Taurus
Mythology, bright stars, and deep-sky highlights.
Constellation
