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6 Trianguli — Double Star in Triangulum

Observable Double Star Excellent (61/100)

Sep: 3.9", Companion: mag 6.7

Magnitude 4.9m DoubleStar Triangulum (Tri) Visible
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1Physical Properties

Magnitude 4.94
Spectral Type G5III+F5V giant
Star Color Orange (B-V 0.78)
Distance 815 ly

2Position & Identifiers

RA 02h 12m 22.3s
Dec +30° 18' 11.0"
Constellation Triangulum (Tri)
HR 642
HIP 10280
HD 13480
SAO 55347
Flamsteed 6 Tri
Variable ID TZ Tri
Double Cat 1697
SIMBAD

3How easy to split?

Primary 4.9 mag Companion 6.7 mag Separation 3.9″
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Telescope Bortle 3 Bortle 4 Bortle 5
80mm refr. Medium+ Medium+ Medium+
150mm Newt. Easy Easy Easy
C8 203mm Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Sep – Nov (peak: Oct)

5Multiple Star System

Separation 3.9″
Companion Mag 6.7
Companion Sp F6V
Position Angle 67°
Star Colors A: Orange B: Yellow
Discoverer STF 227
Binary. Companion F6V.

Separation over time

Period: 5172.5 y Eccentricity: 0.630 Now: 3.9", PA 68° + 0.00" in 5 years
0.00" 1.1" 2.3" 3.4" 4.5" 2025 2030 2035 2040 2045 3.9"

Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.

Eyepiece View

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80x Dawes: 1.9″ TFOV: 0.6°
Realistic = true angular size
N E 67°

A: 4.9 · B: 6.7 · Sep: 3.9″ · PA: 67° · N up, E right

Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″

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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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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

Discover

14Stellar Notes

Amp. 0.075V pulsating?
Comp. A: 14.732d, K 56.5k/s, V0 -19.1k/s, msin3i 1.12, asini 11.4; comp. B: 2.2365d, K 95.4k/s, V0 -19.8k/s, | msin3i 0.905, asini 2.93.
0.007".
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.

NGC 855
Hard+
Elliptical galaxy
Galaxy mag 13.0 2.5° Triangulum
14 Ari
Easy
Easy double, sep 106.2″
Double Star mag 4.98 4.4° Aries
10 Ari
Medium
Tight double — a rewarding split at 1.6″
Double Star mag 5.63 4.8° Aries
C28
NGC 752
Easy
Scattered bright open cluster
Open Cluster mag 5.7 8.1° Andromeda
Show on Map

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