HIP 21958 — Star in Caelum
Observe
1Physical Properties
Magnitude
5.68
Spectral Type
K2III
giant
Star Color
Red
(B-V 1.41)
2Position & Identifiers
RA
04h 43m 09.3s
Dec
-30° 45' 56.0"
Constellation
Caelum
(Cae)
HR
1509
HIP
21958
HD
30080
SAO
195250
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | 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
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Best season
Oct – Dec
(peak: Nov)
5Survey Image
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Explore
6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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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
Caelum
Mythology, bright stars, and deep-sky highlights.
Constellation
