15 Trianguli — Star in Triangulum
Observe
1Physical Properties
Magnitude
5.35
Variable Type
Slow Irregular Variable
Spectral Type
M3IIIa
bright giant
Star Color
Red
(B-V 1.66)
Distance
204 ly
2Position & Identifiers
RA
02h 35m 46.8s
Dec
+34° 41' 15.0"
Constellation
Triangulum
(Tri)
HR
750
HIP
12086
HD
16058
SAO
55687
Flamsteed
15 Tri
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium | Hard+ | Hard |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 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
Sep – Nov
(peak: Oct)
5Survey Image
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6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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14Stellar Notes
Lb?, 5.39 - 5.53V.
Companion, A5, optical.
15
Light Travel Time Machine
16
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
Triangulum
Mythology, bright stars, and deep-sky highlights.
Constellation
