V505 Sagittarii — Variable Star in Sagittarius
Excellent (68/100)
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1Physical Properties
Magnitude
6.48
Range
6.46 - 7.51
Period
28.4 hours
Variable Type
Eclipsing Binary (Algol-type)
Spectral Type
A0V+F8IV
Star Color
Blue-white
(B-V 0.14)
2Position & Identifiers
RA
19h 53m 06.4s
Dec
-14° 36' 11.0"
Constellation
Sagittarius
(Sgr)
HR
7571
HIP
97849
HD
187949
SAO
163080
Variable ID
V505 Sgr
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3How easy to follow?
Magnitude
6.5 – 7.5 mag
Amplitude
1.0 mag
Period
1.18 d
Type
EA/SD
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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+ | Medium |
| 150 mm telescope 150mm scope | Medium+ | Medium+ | Medium+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
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Best season
Jun – Aug
(peak: Jul)
5Survey Image
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6Light Curve
7Comparison Stars for V505 Sgr (6.5–7.5)
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
EA 6.48 - 7.51V, 1.18287511d. Period decreases about 0.49s/y. i 80.3d. Contact binary. Masses 2.2 and 1.2 solar, radii | both about 2.2.
Speckle interferometry indicates companion at 0.291", probably not the same as the SB or occultation binary.
6.6 - 8.6v, sep. 0.0002", 1.1829d, K 104k/s, V0 -2k/s, asini 1.69; vsini of secondary 50k/s.
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.
IC 4895
Galaxy
Galaxy
mag 8.0
2.0°
Sagittarius
V1401 Aql
Semi-regular variable, range 6.2–6.5
Variable Star
mag 6.34
4.2°
Aquila
M75
NGC 6864
Compact globular cluster
Globular Cluster
mag 8.6
7.9°
Sagittarius
U Aql
Pulsating variable, period 7.0d
Variable Star
mag 6.61
9.5°
Aquila
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