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Alpha Persei Cluster — Open Cluster in Perseus

Open Cluster Excellent (70/100)
Magnitude 1.2m OpenCluster Perseus Visible
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1Properties

Magnitude 1.2
Angular Size 300 arcmin
Distance 557 ly
Open Cluster

Position & Identifiers

RA 03h 24m 19.0s
Dec +49° 51' 42.0"
Constellation Perseus
Catalog Mel 20
Physical size
49 light-years across — tens of light-years across — wider than the solar neighbourhood

2How easy to spot?

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Telescope Bortle 3 Bortle 4 Bortle 5
80mm refr. Easy Easy Easy
150mm Newt. Easy Easy Easy
C8 203mm Easy Easy Easy
Easy Medium Hard Very hard Impossible

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

Medium on Seestar S50

3Visibility

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Best season Oct – Dec (peak: Nov)

4 Eyepiece View

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19x TFOV: 2.3° Lim. mag: 13.6
N E

Alpha Persei Cluster · 300.0′ diameter

5 Best Magnification

Discover

6

Light Travel Time Machine

7

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.

Mirfak
Alpha Per
Easy
Bright naked-eye star, mag 1.8
Star mag 1.79 0.0° Perseus
NGC 1245
Easy
Open cluster
Open Cluster mag 8.4 3.1° Perseus
NGC 1220
Hard+
Open cluster
Open Cluster mag 12.0 4.0° Perseus
NGC 1444
Easy
Rich open cluster
Open Cluster mag 6.6 4.8° Perseus
NGC 1496
Easy
Open cluster
Open Cluster mag 10.0 6.9° Perseus
NGC 1175
Hard+
Bright spiral galaxy
Galaxy mag 12.8 8.3° Perseus
Algol
HIP 14576; Beta Persei; 26 Persei
Easy
Eclipsing binary, period 2.9d
Variable Star mag 2.12 9.3° Perseus
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