Y Ophiuchi — Variable Star in Ophiuchus
Excellent (64/100)
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1Physical Properties
Magnitude
6.21
Range
5.87 - 6.34
Period
17.1 days
Variable Type
Classical Cepheid
Spectral Type
F8Ib-G3Ib
supergiant
Star Color
Red
(B-V 1.40)
2Position & Identifiers
RA
17h 52m 38.8s
Dec
-06° 08' 37.0"
Constellation
Ophiuchus
(Oph)
HR
6661
HIP
87495
HD
162714
SAO
141926
Variable ID
Y Oph
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.9 – 6.5 mag
Amplitude
0.6 mag
Period
17.13 d
Type
DCEP
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | 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
May – Jul
(peak: Jun)
5Survey Image
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6Light Curve
7Comparison Stars for Y Oph (5.9–6.5)
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
Delta Cep 5.87 - 6.46V, 17.12413d, period varies. Atypical light curve. Possibly SB.
Probably not IR source.
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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Variable Stars — A Guide for Observers
A practical guide to visual observation of variable stars: estimating magnitudes, finding comparison stars, recording data, and contributing to science with AAVSO.
Article
Ophiuchus
Mythology, bright stars, and deep-sky highlights.
Constellation
