Observe
1Physical Properties
Magnitude
5.40
Range
5.18 - 5.54
Period
36 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M4IIIa
Star Color
Red
(B-V 1.63)
2Position & Identifiers
RA
16h 17m 15.3s
Dec
+59° 45' 18.0"
Constellation
Draco
(Dra)
HR
6086
HIP
79804
HD
147232
Variable ID
AT Dra
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.2 – 5.5 mag
Amplitude
0.4 mag
Period
35.57 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard+ | V. hard |
| 50 mm finder 50mm finder | Hard+ | Hard+ | Hard+ |
| 150 mm telescope 150mm scope | Hard+ | Hard+ | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Out of reach for typical amateur telescopes, even at Bortle 3.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Light Curve
6Comparison Stars for AT Dra (5.2–5.5)
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
Lb 6.8 - 7.5p.
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.
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A practical guide to visual observation of variable stars: estimating magnitudes, finding comparison stars, recording data, and contributing to science with AAVSO.
Article
Draco
Mythology, bright stars, and deep-sky highlights.
Constellation
