Menu

Mu Normae — Star in Norma

Magnitude 4.9–5.0m Star Norma (Nor) Visible
Star Map
+ List + Plan

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
SIMBAD

3How easy to spot?

Sign in and configure your equipment and default location to see a personalized row.
Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium Medium Hard+
50mm finder Easy Easy Easy
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 Apr – Jun (peak: May)

5Survey Image

Loading survey image…

Explore

6

Size Comparison

Querying VizieR for stellar data…
7

Compare Stars

8

Spectral Classification

9

Hertzsprung-Russell Diagram

Loading HR diagram…
Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
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
Easy
Open cluster
Open Cluster mag 7.0 0.0° Norma
V918 Sco
Easy
Hot blue O-type star
Star mag 5.47 1.3° Scorpius
Epsilon Nor
Easy
Easy double, sep 22.9″
Double Star mag 4.47 3.7° Norma
V919 Sco
Easy
Wolf-Rayet star — rare, hot emission spectrum
Star mag 6.49 4.0° Scorpius
NGC 6164
Easy
Planetary nebula — try an OIII filter
Planetary Nebula mag 6.71 4.0° Norma
V861 Sco
Medium
Eclipsing binary, period 7.8d
Variable Star mag 6.15 5.3° Scorpius
Show on Map

Explore Nightbase

Related knowledge, tools, and stories — no observation planning required.

Arthur Eddington
1919 eclipse expedition confirming general relativity; first theory of stellar interiors; the Eddington limit
Biography
The Life of Stars
From birth in a nebula to spectacular death — how stars are born, shine, swell, and die, and how to read the clues in their starlight.
Article
Norma
Mythology, bright stars, and deep-sky highlights.
Constellation
}