Nu Canis Majoris — Double Star in Canis Major
HIP 31700; Nu Canis Majoris; 8 Canis Majoris
Fair (25/100)
Observe
1Physical Properties
Magnitude
4.43
Spectral Type
K1-II-III
Star Color
Orange
(B-V 1.15)
Distance
251 ly
2Position & Identifiers
RA
06h 37m 53.4s
Dec
-18° 14' 15.0"
Constellation
Canis Major
(CMa)
HR
2443
HIP
31700
HD
47442
SAO
151730
Bayer
Nu
Flamsteed
8 CMa
Querying VizieR catalog...
3How easy to split?
Primary
4.4 mag
Companion
8.2 mag
Separation
1.2″
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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 380 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Nov – Jan
(peak: Dec)
5Multiple Star System
Separation
1.2″
Companion Mag
8.2
Position Angle
7°
Star Colors
A: Orange
Discoverer
HDS 915
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.4 · B: 8.2 · Sep: 1.2″ · PA: 7° · N up, E right
Unresolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
7
Size Comparison
Querying VizieR for stellar data…
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
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11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
UMa stream.
Also classified K1III, K3-III Fe-0.5.
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.
Nu CMa
HIP 31564; Nu Canis Majoris; 6 Canis Majoris
Easy double, sep 17.4″
Double Star
mag 5.70
0.6°
Canis Major
NGC 2296
Elliptical galaxy
Galaxy
mag 13.0
2.9°
Canis Major
M41
Little Beehive Cluster
Rich open cluster
Open Cluster
mag 4.5
3.2°
Canis Major
Murzim
Beta CMa
Hot blue O-type star
Double Star
mag 1.98
3.6°
Canis Major
Mu CMa
Colorful double, sep 2.8″
Double Star
mag 5.00
6.1°
Canis Major
S Lep
Semi-regular variable, range 6.0–7.6
Variable Star
mag 6.95
9.6°
Lepus
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