3 Sagittarii — Variable Star in Sagittarius
Excellent (70/100)
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1Physical Properties
Magnitude
4.54
Range
4.22 - 4.86
Period
7.0 days
Variable Type
Classical Cepheid
Spectral Type
F7II
bright giant
Star Color
Orange
(B-V 0.80)
Distance
93 ly
2Position & Identifiers
RA
17h 47m 33.6s
Dec
-27° 49' 51.0"
Constellation
Sagittarius
(Sgr)
HR
6616
HIP
87072
HD
161592
SAO
185755
Flamsteed
3 Sgr
Variable ID
X Sgr
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3How easy to follow?
Magnitude
4.2 – 4.8 mag
Amplitude
0.6 mag
Period
7.01 d
Type
DCEP
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | Hard |
| 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
Set a location in User Settings to see visibility data.
Best season
May – Jul
(peak: Jun)
5Survey Image
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6Light Curve
7Comparison Stars for 3 Sgr (4.2–4.8)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
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
Discover
16Stellar Notes
CDelta 4.24 - 4.84V, 7.01225d.
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.
NGC 6451
Open cluster
Open Cluster
mag 8.0
2.5°
Scorpius
NGC 6522
Compact globular cluster
Globular Cluster
mag 8.6
4.1°
Sagittarius
Gamma Sgr
HIP 88567; Gamma1 Sagittarii
Pulsating variable, period 7.6d
Variable Star
mag 4.69
4.2°
Sagittarius
4 Sgr
Colorful double, sep 3.7″
Double Star
mag 4.76
4.9°
Sagittarius
RS Sgr
Eclipsing binary, period 2.4d
Variable Star
mag 6.16
9.0°
Sagittarius
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