Pi Mensae — Star in Mensa
Observe
1Physical Properties
Magnitude
5.65
Spectral Type
G1V
Star Color
Yellow
(B-V 0.60)
Distance
74 ly
2Position & Identifiers
RA
05h 37m 09.8s
Dec
-80° 28' 09.0"
Constellation
Mensa
(Men)
HR
2022
HIP
26394
HD
39091
SAO
258421
Bayer
Pi
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
Set a location in User Settings to see visibility data.
Best season
Nov – Jan
(peak: Dec)
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
14
Exoplanets
3 known planets
View in 3D
View this system in the 3D Orrery
Interactive Keplerian orbits, procedural planet textures, habitable zone.
| Planet | Radius | Mass | Period | Distance |
|---|---|---|---|---|
| pi Men c | 2.02R⊕ | 3.6M⊕ | 6.3d | 60ly |
| pi Men d | 3.72R⊕ | 13.4M⊕ | 124.6d | 60ly |
| HD 39091 b | 12.30R⊕ | 14.10M♃ | 5.7yr | 60ly |
Habitable Zone
Size & Mass Comparison
About exoplanets — how we find them and which host stars you can observe
Discover
15Stellar Notes
61 Cyg group.
16
Light Travel Time Machine
17
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.
NGC 2012
Elliptical galaxy
Galaxy
mag 12.97
0.9°
Mensa
NGC 1841
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 12.0
3.9°
Mensa
TZ Men
Eclipsing binary, period 8.6d
Variable Star
mag 6.20
4.3°
Mensa
NGC 2203
Open cluster
Open Cluster
mag 11.29
5.2°
Mensa
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Mensa
Mythology, bright stars, and deep-sky highlights.
Constellation
