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Epsilon Arietis — Double Star in Aries

HIP 13914; Epsilon Arietis; 48 Arietis

Observable Double Star Fair (30/100)

Sep: 1.3", Companion: mag 5.6

Magnitude 4.6m DoubleStar Aries (Ari) Visible
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1Physical Properties

Magnitude 4.63
Spectral Type A2V s
Star Color White (B-V 0.04)
Distance 652 ly

2Position & Identifiers

RA 02h 59m 12.7s
Dec +21° 20' 25.0"
Constellation Aries (Ari)
HR 887
HIP 13914
HD 18520
Bayer Epsilon
Flamsteed 48 Ari
Double Cat 2257
SIMBAD Wikipedia

3How easy to split?

Primary 4.6 mag Companion 5.6 mag Separation 1.3″
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Telescope Bortle 3 Bortle 4 Bortle 5
80mm refr. V. hard+ V. hard+ V. hard+
150mm Newt. Hard+ Hard+ Hard+
C8 203mm Medium Medium Medium
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 Triple

Components 3 (triple)
Component IDs AB
Separation 1.3″
Companion Mag 5.6
Companion Sp A2Vs
Position Angle 211°
Star Colors A: White B: White
Discoverer STF 333
Binary with HR 888. Mag. and colors for combined light.

Separation over time

Period: 710.5 y Eccentricity: 0.435 Now: 1.3", PA 211° -0.05" in 5 years
0.00" 0.38" 0.75" 1.1" 1.5" 2025 2030 2035 2040 2045 1.3"

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 211°

A: 4.6 · B: 5.6 · Sep: 1.3″ · PA: 211° · N up, E right

Unresolved · 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

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14Stellar Notes

Uncertain if HR 887 or 888 is the variable suspect.
0.012".
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.

Rho Ari
HIP 13654; Rho2 Arietis; 45 Arietis
Hard+
Semi-regular variable, range 5.6–6.0
Variable Star mag 5.91 3.1° Aries
NGC 1156
Hard+
Galaxy
Galaxy mag 11.7 3.9° Aries
Pi Ari
Easy
Easy double, sep 3.3″
Double Star mag 5.22 4.5° Aries
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