44 Bootis — Variable Star in Boötes
Good (57/100)
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1Physical Properties
Magnitude
4.76
Range
4.7 - 4.9
Period
6.4 hours
Variable Type
Eclipsing Binary (W UMa-type)
Spectral Type
F9-G1Vn
Star Color
Yellow
(B-V 0.65)
Distance
38 ly
2Position & Identifiers
RA
15h 03m 47.4s
Dec
+47° 39' 16.0"
Constellation
Boötes
(Boo)
HR
5618
HIP
73695
HD
133640
SAO
45357
Flamsteed
44 Boo
Variable ID
i Boo
Double Cat
9494
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3How easy to follow?
Magnitude
6.5 – 7.1 mag
Amplitude
0.6 mag
Period
6.4 h
Type
EW/KW
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard | Imp. | Imp. |
| 50 mm finder 50mm finder | Medium | Medium | Hard+ |
| 150 mm telescope 150mm scope | Medium | Medium | Medium |
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
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6Light Curve
7Comparison Stars for 44 Boo (6.5–7.1)
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
ADS 9494B, EW 6.5 - 7.10v, 0.2678160d. Period changes with orbital motion. Variation in light curve may be caused by | mass transfer between close pair. Reddening at max. due to ADS 9494A. Component A may vary up to 0.09m.
5.3 F5V, var. G2V+G2V, 225.0y, a = 3.772". Combined mag., colors. Combined mass 2.1 solar.
ADS 9494B, 0.2678d, K 115.4k/s, V0 +3.4k/s, msin3i 0.772, asini 0.425.
0.073".
17
Light Travel Time Machine
18
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.
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Article
Boötes
Mythology, bright stars, and deep-sky highlights.
Constellation
