Menu

NGC 225 — Open Cluster in Cassiopeia

Open Cluster Good (56/100)
Magnitude 7.0m OpenCluster Cassiopeia (Cas) Visible
Star Map
+ List + Plan Star Hop

Observe

1Properties

Magnitude 7.0
Angular Size 4.2′
Cl, L, lC, st 9...10

Position & Identifiers

RA 00h 43m 36.4s
Dec +61° 46' 00.8"
Constellation Cassiopeia (Cas)
Catalog NGC 225
Physical size
2.7 light-years across — comparable to the Sun's nearest-neighbour distance

2How easy to spot?

Sign in and configure your equipment and default location to see a personalized row.
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
At 150mm under B5 skies you should resolve about 12 of 28 members.

3Visibility

Set a location in User Settings to see visibility data.

Best season Aug – Oct (peak: Sep)

4 Eyepiece View

Log in to set your own equipment
125x TFOV: 0.4° Lim. mag: 13.6
N E

NGC 225 · 4.2′ diameter

5 Best Magnification

6Where this cluster sits in time

1 Myr 10 Myr 100 Myr 1 Gyr 10 Gyr NGC 2362 Pleiades Hyades M67 NGC 188 NGC 225 288 Myr

Open clusters span more than four orders of magnitude in age — from newborn OB associations to ancient, metal-rich survivors.

7 Colour-Magnitude Diagram

A cluster's colour-magnitude diagram reveals its age: the bluer the turn-off point where the main sequence bends into red giants, the younger the cluster.

Loading member data…

Each point is a Gaia-DR3 member. Colour encodes spectral type; size reflects membership probability.

Explore

8 Classification Decoder

}