R Trianguli — Variable Star in Triangulum
Showpiece (80/100)
Observe
1Physical Properties
Magnitude
5.30
Range
5.4 - 12.6
Period
267 days
Variable Type
Mira (Long-period Pulsating)
Spectral Type
M4IIIe
bright giant
Star Color
Red
(B-V 1.55)
Distance
408 ly
2Position & Identifiers
RA
02h 37m 02.5s
Dec
+34° 15' 50.0"
Constellation
Triangulum
(Tri)
HR
758
HIP
12193
HD
16210
Variable ID
R Tri
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.4 – 12.6 mag
Amplitude
7.2 mag
Period
267 d
Type
M
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | Imp. | Imp. | Imp. |
| 150 mm telescope 150mm scope | Hard+ | Hard | V. hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
To reach "Medium" at Bortle 3, you'd need at least a 190 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Sep – Nov
(peak: Oct)
5Survey Image
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6Light Curve
7Comparison Stars for R Tri (5.4–12.6)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
Discover
16Stellar Notes
M 5.4 - 12.6v, 266.43d.
IR source.
17
Light Travel Time Machine
18
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.
NGC 1060
Elliptical galaxy
Galaxy
mag 13.0
2.3°
Triangulum
Gorgonea Tertia
HIP 14354; Rho Persei; 25 Persei
Semi-regular variable, range 3.3–4.0
Variable Star
mag 3.39
7.3°
Perseus
M34
NGC 1039
Open cluster
Open Cluster
mag 5.2
8.5°
Perseus
Algol
HIP 14576; Beta Persei; 26 Persei
Eclipsing binary, period 2.9d
Variable Star
mag 2.12
9.1°
Perseus
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Article
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