29 Canis Majoris — Variable Star in Canis Major
Excellent (64/100)
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1Physical Properties
Magnitude
4.98
Range
4.84 - 5.33
Period
4.4 days
Variable Type
Eclipsing Binary (Beta Lyrae-type)
Spectral Type
O7Ia:fp
supergiant
Star Color
Blue-white
(B-V -0.15)
2Position & Identifiers
RA
07h 18m 40.3s
Dec
-24° 33' 32.0"
Constellation
Canis Major
(CMa)
HR
2781
HIP
35412
HD
57060
SAO
173444
Flamsteed
29 CMa
Variable ID
UW CMa
Querying VizieR catalog...
3How easy to follow?
Magnitude
4.8 – 5.3 mag
Amplitude
0.5 mag
Period
4.39 d
Type
EB/KE
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard | V. hard+ | V. hard+ |
| 50 mm finder 50mm finder | Hard+ | Hard+ | Hard+ |
| 150 mm telescope 150mm scope | Hard+ | Hard+ | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Out of reach for typical amateur telescopes, even at Bortle 3.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Dec – Feb
(peak: Jan)
5Survey Image
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6Light Curve
7Comparison Stars for 29 CMa (4.8–5.3)
Nearby stable stars for estimating brightness (AAVSO)
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8
Size Comparison
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9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
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16Stellar Notes
EB 4.84 - 5.33V, 4.5 - 4.8p, amp. 0.45V, 4.393407d. Sp. lines vary within about 1 hr. Variable polarization.
4.3934d, K 222.5k/s, V0 +13.5k/s, asini 13.4. Alternate orbit 4.3934d, K 242k/s, V0 +13.7k/s, asini 14.6. | Nearly equal components. Mass loss from primary; asymmetrically expanding atmosphere.
Color excess E(B-V) = +0.18.
In HII reg. S310; probable runaway star; in cluster NGC 2362.
Weak C IV for its luminosity class of Ia. Variously classified O7f, O7.5If, O8.5If, O7e + O7:, O8f + O8f.
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.
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