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Theta Trianguli Australis — Star in Triangulum Australe

Magnitude 5.5m Star Triangulum Australe (TrA) Visible
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1Physical Properties

Magnitude 5.52
Spectral Type G8-K0III
Star Color Orange (B-V 0.93)
Distance 233 ly

2Position & Identifiers

RA 16h 35m 44.8s
Dec -65° 29' 43.0"
Constellation Triangulum Australe (TrA)
HR 6151
HIP 81252
HD 148890
SAO 253614
Bayer Theta
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium Hard+ Hard
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 Apr – Jun (peak: May)

5Survey Image

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6

Size Comparison

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7

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8

Spectral Classification

9

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
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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14

Light Travel Time Machine

15

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.

Atria
HIP 82273; Alpha Trianguli Australis
Easy
Bright naked-eye star, mag 1.9
Star mag 1.92 3.7° Triangulum Australe
S TrA
Medium
Pulsating variable, period 6.3d
Variable Star mag 6.41 4.1° Triangulum Australe
NGC 6362
Easy
Globular cluster — dense ball of ancient stars
Globular Cluster mag 8.3 5.8° Ara
NGC 5938
Hard+
Barred spiral galaxy
Galaxy mag 11.49 6.1° Triangulum Australe
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