Mu Normae — Double Star in Norma
Observe
1Physical Properties
Magnitude
4.94
Range
4.87 - 4.94
Variable Type
ACYG:
Spectral Type
B0Ia
supergiant
Star Color
White
(B-V 0.05)
2Position & Identifiers
RA
16h 34m 05.0s
Dec
-44° 02' 43.0"
Constellation
Norma
(Nor)
HR
6155
HIP
81122
HD
149038
SAO
226900
Bayer
Mu
Variable ID
Mu Nor
Querying VizieR catalog...
3How easy to split?
Primary
4.9 mag
Companion
10.6 mag
Separation
1.5″
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | V. hard | V. hard | V. hard |
| 150 mm Newton 150mm Newt. | V. hard | V. hard | V. hard |
| Celestron C8 (203 mm SCT) C8 203mm | V. hard | V. hard | V. hard |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
To reach "Medium" at Bortle 3, you'd need at least a 640 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Multiple Star System
Separation
1.5″
Companion Mag
10.6
Position Angle
158°
Star Colors
A: White
Discoverer
SNA 41
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.9 · B: 10.6 · Sep: 1.5″ · PA: 158° · N up, E right
Unresolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
6
Size Comparison
Querying VizieR for stellar data…
7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
Loading HR diagram…
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
14Stellar Notes
Alpha Cyg? 4.87 - 4.98V.
Color excess E(B-V) = +0.36.
Ara OB1a; in cluster NGC 6169 #1.
Also classified O9.7Iab.
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 6169
Open cluster
Open Cluster
mag 7.0
0.0°
Norma
V918 Sco
Hot blue O-type star
Double Star
mag 5.47
1.3°
Scorpius
Epsilon Nor
Easy double, sep 22.9″
Double Star
mag 4.47
3.7°
Norma
NGC 6164
Planetary nebula — try an OIII filter
Planetary Nebula
mag 6.71
4.0°
Norma
V861 Sco
Eclipsing binary, period 7.8d
Variable Star
mag 6.15
5.3°
Scorpius
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