Observe
1Physical Properties
Magnitude
6.25
Range
5.41 - 6.72
Period
59 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M6III
Star Color
Red
(B-V 1.48)
2Position & Identifiers
RA
20h 37m 54.6s
Dec
+18° 16' 09.0"
Constellation
Delphinus
(Del)
HR
7886
HIP
101810
HD
196610
Variable ID
EU Del
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.8 – 6.9 mag
Amplitude
1.1 mag
Period
58.63 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | Imp. |
| 50 mm finder 50mm finder | Medium+ | Medium+ | Medium+ |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
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
Jun – Aug
(peak: Jul)
5Light Curve
6Comparison Stars for EU Del (5.8–6.9)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
7
Size Comparison
Querying VizieR for stellar data…
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
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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
Discover
15Stellar Notes
SRb 5.79 - 6.9v, 59.7d. Amp. 0.36V, 0.12(B-V), 0.19(U-B), but varies.
Survey Image
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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.
U Del
Semi-regular variable, range 6.1–7.6
Variable Star
mag 6.38
1.8°
Delphinus
Gamma Del
HIP 102531; Gamma1 Delphini; 12 Delphini
Colorful double, sep 9.8″
Double Star
mag 5.14
3.0°
Delphinus
C42
NGC 7006
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 10.6
6.0°
Delphinus
22 Vul
Observable variable star
Variable Star
mag 5.15
7.4°
Vulpecula
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