Omega Canis Majoris — Star in Canis Major
Observe
1Physical Properties
Magnitude
3.85
Range
3.54 - 4.18
Variable Type
Gamma Cassiopeiae (Eruptive Be Star)
Spectral Type
B2.5Ve
Star Color
Blue
(B-V -0.17)
Distance
909 ly
2Position & Identifiers
RA
07h 14m 48.7s
Dec
-26° 46' 22.0"
Constellation
Canis Major
(CMa)
HR
2749
HIP
35037
HD
56139
SAO
173282
Bayer
Omega
Flamsteed
28 CMa
Variable ID
Ome CMa
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Medium+ | Medium+ |
| 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
Dec – Feb
(peak: Jan)
5Survey Image
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Explore
7
Size Comparison
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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
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15Stellar Notes
Gamma Cas 3.60 - 4.18V, cycles 20 - 22 hrs. Also amp. 0.06V on time scale of 5d reported. Hydrogen emission varies | with period 1.3667d (possibly a rotation period).
+22 to -10k/s change in 0.2d. Expanding circumstellar shell. Pole on. 1.36d period.
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.
GY CMa
Hot blue O-type star
Star
mag 6.12
0.6°
Canis Major
NGC 2354
Rich open cluster
Open Cluster
mag 6.5
1.1°
Canis Major
Tau CMa
Hot blue O-type star
Double Star
mag 4.40
2.0°
Canis Major
29 CMa
Eclipsing binary, period 4.4d
Variable Star
mag 4.98
2.4°
Canis Major
NGC 2325
Elliptical galaxy
Galaxy
mag 11.2
3.3°
Canis Major
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