U Hydrae — Variable Star in Hydra
Good (58/100)
Observe
1Physical Properties
Magnitude
4.82
Range
4.56 - 5.40
Period
389 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
C5II
bright giant
Star Color
Deep ruby red
(B-V 2.68)
2Position & Identifiers
RA
10h 37m 33.2s
Dec
-13° 23' 04.0"
Constellation
Hydra
(Hya)
HR
4163
HIP
52009
HD
92055
SAO
156110
Variable ID
U Hya
Querying VizieR catalog...
3How easy to follow?
Magnitude
4.6 – 5.4 mag
Amplitude
0.8 mag
Period
389.4 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | V. 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
Set a location in User Settings to see visibility data.
Best season
Jan – Mar
(peak: Feb)
5Survey Image
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6Light Curve
7Comparison Stars for U Hya (4.6–5.4)
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
SRb 7.0 - 9.2p, 7.0 - 9.4B, about 450d. Amp. 0.12V in one cycle in 1971.
Technetium star.
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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Article
Hydra
Mythology, bright stars, and deep-sky highlights.
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