Gamma Andromedae — Double Star in Andromeda
HIP 9640; Gamma2 Andromedae; 57 Andromedae
Showpiece (89/100)
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1Physical Properties
Magnitude
4.84
Spectral Type
K3II
bright giant
Star Color
White
(B-V 0.03)
Distance
352 ly
2Position & Identifiers
RA
02h 03m 54.7s
Dec
+42° 19' 51.0"
Constellation
Andromeda
(And)
HR
604
HIP
9640
HD
12534
SAO
37735
Bayer
Gamma2
Flamsteed
57 And
Double Cat
1630
Querying VizieR catalog...
3How easy to split?
Primary
4.8 mag
Companion
5.0 mag
Separation
9.6″
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Easy | Easy | Easy |
| 150 mm Newton 150mm Newt. | Easy | Easy | Easy |
| Celestron C8 (203 mm SCT) 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 Quadruple
Components
4 (quadruple)
Component IDs
AxBC
Separation
9.6″
Companion Mag
5.0
Star Colors
A: White
C: Red
BC 5.5 B8V, 6.3 A0V, 61.1y, a = 0.296". ADS 1630BC CPM with HR 603. Component D, 15v at 28". Possibly also CPM with | BD+41d408 at 53'.
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.8 · B: 5.0 · Sep: 9.6″ · PA: ? · 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
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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
ADS 1630B, 2.67d, K 141k/s, V0 +2.5k/s, msin3i 1.76, asini 4.95; vsini of both components 70k/s.
0.010".
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.
Almaak
HIP 9640; Gamma1 Andromedae; 57 Andromedae
Bright naked-eye star, mag 2.3
Star
mag 2.26
0.0°
Andromeda
C23
NGC 891
Edge-on galaxy
Galaxy
mag 9.9
3.4°
Andromeda
59 And
Easy double, sep 16.6″
Double Star
mag 5.63
3.5°
Andromeda
NGC 752
Scattered bright open cluster
Open Cluster
mag 5.7
4.7°
Andromeda
M76
Little Dumbbell Nebula
Planetary nebula — try an OIII filter
Planetary Nebula
mag 10.1
9.9°
Perseus
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