TW Horologii — Variable Star in Horologium
Good (52/100)
Observe
1Physical Properties
Magnitude
5.74
Range
5.52 - 5.95
Period
270 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
C5II
bright giant
Star Color
Deep ruby red
(B-V 2.28)
2Position & Identifiers
RA
03h 12m 33.2s
Dec
-57° 19' 18.0"
Constellation
Horologium
(Hor)
HR
977
HIP
14930
HD
20234
SAO
233037
Variable ID
TW Hor
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.5 – 6.0 mag
Amplitude
0.4 mag
Period
270.3 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | V. hard |
| 50 mm finder 50mm finder | Hard+ | Hard+ | Hard+ |
| 150 mm telescope 150mm scope | Hard+ | Hard+ | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Out of reach for typical amateur telescopes, even at Bortle 3.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
5Survey Image
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6Light Curve
7Comparison Stars for TW Hor (5.5–6.0)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
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
Discover
16Stellar Notes
SRb 5.52 - 5.95V, about 158d.
Also classified C7,2 (N0).
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
Horologium
Mythology, bright stars, and deep-sky highlights.
Constellation
