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Epsilon Aquilae — Star in Aquila

Magnitude 4.0m Star Aquila (Aql) Visible
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1Physical Properties

Magnitude 4.02
Spectral Type K1-IIICN0.5Ba0.2
Star Color Orange (B-V 1.08)

2Position & Identifiers

RA 18h 59m 37.4s
Dec +15° 04' 06.0"
Constellation Aquila (Aql)
HR 7176
HIP 93244
HD 176411
SAO 104318
Bayer Epsilon
Flamsteed 13 Aql
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Easy Medium+ Medium
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season May – Jul (peak: Jun)

5Survey Image

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7

Size Comparison

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8

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9

Spectral Classification

10

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
11

Stellar Lifecycle

12

Blackbody Spectrum

13

Stellar Absorption Spectrum

Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.

14

Stellar Fusion

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15Stellar Notes

V magnitudes scatter from 5.56 to 5.81, B-V from +0.35 to +0.45, U-B from -0.01 to +0.04.
Deneb el Okab; Deneb. Names combined with HR 7235.

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.

FF Aql
Medium
Pulsating variable, period 4.5d
Variable Star mag 5.38 2.3° Aquila
NGC 6738
Easy
Open cluster
Open Cluster mag 8.0 3.5° Aquila
NGC 6660
Hard+
Bright spiral galaxy
Galaxy mag 12.36 9.8° Hercules
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