Eta Mensae — Star in Mensa
Observe
1Physical Properties
Magnitude
5.47
Spectral Type
K4III
giant
Star Color
Red
(B-V 1.52)
Distance
125 ly
2Position & Identifiers
RA
04h 55m 11.2s
Dec
-74° 56' 13.0"
Constellation
Mensa
(Men)
HR
1629
HIP
22871
HD
32440
SAO
256145
Bayer
Eta
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium | 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
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
5Survey Image
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Explore
6
Size Comparison
Querying VizieR for stellar data…
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
Discover
14
Light Travel Time Machine
15
Relativistic Travel
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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Biography
Mensa
Mythology, bright stars, and deep-sky highlights.
Constellation
The Hertzsprung-Russell Diagram — Reading Stars Like a Map
The HR diagram turns the night sky into a physics map: every named star has a spot, every spot tells you mass, age, and fate. A guide for amateur observers.
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