Y Tauri — Variable Star in Taurus
Good (54/100)
Observe
1Physical Properties
Magnitude
6.95
Range
6.4 - 7.3
Period
245 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
C5II
bright giant
Star Color
Deep ruby red
(B-V 3.03)
2Position & Identifiers
RA
05h 45m 39.4s
Dec
+20° 41' 42.0"
Constellation
Taurus
(Tau)
HR
1977
HIP
27181
HD
38307
SAO
77516
Variable ID
Y Tau
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3How easy to follow?
Magnitude
6.4 – 7.3 mag
Amplitude
0.9 mag
Period
245 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard | Imp. | Imp. |
| 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
Set a location in User Settings to see visibility data.
Best season
Nov – Jan
(peak: Dec)
5Survey Image
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6Light Curve
7Comparison Stars for Y Tau (6.4–7.3)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
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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
SRa 10.1 - 12.2p, 240.9d. Mean mag. varies in period 1750d.
Sign uncertain.
Occultation diam. = 0.0080 - 0.0088".
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.
M1
Crab Nebula
Supernova remnant
Supernova Remnant
mag 8.4
2.9°
Taurus
119 Tau
Semi-regular variable, range 4.2–4.6
Variable Star
mag 4.38
3.8°
Taurus
NGC 2129
Rich open cluster
Open Cluster
mag 6.7
4.4°
Gemini
3 Gem
Variable star, range 7.0–10.0
Variable Star
mag 5.75
6.1°
Gemini
TV Gem
Variable star, range 6.3–7.5
Variable Star
mag 6.56
6.2°
Gemini
6 Gem
Mira-type variable, range 5.7–8.1
Variable Star
mag 6.39
6.6°
Gemini
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