Eta Aquilae — Variable Star in Aquila
Excellent (72/100)
Observe
1Physical Properties
Magnitude
3.90
Range
3.49 - 4.3
Period
7.2 days
Variable Type
Classical Cepheid
Spectral Type
F7-G2Ib
Star Color
Yellow
(B-V 0.89)
(reddened by dust)
Distance
1,382 ly
2Position & Identifiers
RA
19h 52m 28.4s
Dec
+01° 00' 20.0"
Constellation
Aquila
(Aql)
HR
7570
HIP
97804
HD
187929
SAO
125159
Bayer
Eta
Flamsteed
55 Aql
Variable ID
Eta Aql
Querying VizieR catalog...
3How easy to follow?
Magnitude
3.5 – 4.3 mag
Amplitude
0.8 mag
Period
7.18 d
Type
DCEP
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium | 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
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Best season
Jun – Aug
(peak: Jul)
5Survey Image
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6Light Curve
7Comparison Stars for Eta Aql (3.5–4.3)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
9
Size Comparison
Querying VizieR for stellar data…
10
Compare Stars
11
Spectral Classification
12
Hertzsprung-Russell Diagram
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13
Stellar Lifecycle
14
Blackbody Spectrum
15
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
16
Stellar Fusion
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17Stellar Notes
Discovered by Pigott in 1784. CDelta 3.50 - 4.30V, 7.176641d. Period changes. Variable He 10830 in emission and | absorption.
Also classified F6Ib-G4Ib. UV suggests A0V companion.
18
Light Travel Time Machine
19
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
Aquila
Mythology, bright stars, and deep-sky highlights.
Constellation
