TU Horologii — Star in Horologium
Observe
1Physical Properties
Magnitude
5.99
Range
5.90 - 6.04
Period
22.5 hours
Variable Type
Ellipsoidal Variable
Spectral Type
A1V
Star Color
White
(B-V 0.11)
2Position & Identifiers
RA
03h 30m 37.0s
Dec
-47° 22' 31.0"
Constellation
Horologium
(Hor)
HR
1081
HIP
16339
HD
21981
Variable ID
TU Hor
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | V. hard+ |
| 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
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
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5
Size Comparison
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6
Compare Stars
7
Spectral Classification
8
Hertzsprung-Russell Diagram
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9
Stellar Lifecycle
10
Blackbody Spectrum
11
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
12
Stellar Fusion
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13Stellar Notes
Ell 5.90 - 6.04V, 0.935971d.
0.936d reported with no other elements.
Also classified A2V + K.
Survey Image
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Visibility scores assume a 150 mm Newton at Bortle 4.
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Horologium
Mythology, bright stars, and deep-sky highlights.
Constellation
