Menu

NGC 1528 — Open Cluster in Perseus

Open Cluster Excellent (65/100)
Magnitude 6.4m OpenCluster Perseus (Per) Visible
Star Map
+ List + Plan Star Hop

About NGC 1528

Description

NGC 1528 is a bright, moderately rich open cluster in Perseus, about 2,500 light-years away. At magnitude 6.4 it sits just on the threshold of naked-eye visibility from a dark site, and in binoculars it displays perhaps 40 to 60 stars scattered across 24 arcminutes — roughly the width of the full Moon. The cluster lies in a rich Milky Way field between the famous Perseus OB2 association and the Double Cluster, and it pairs naturally with its fainter neighbor NGC 1545, which lies less than a degree to the south-southwest. Both clusters are young (~300 million years) and share the general population of hot B-type stars typical of Perseus.

Observing Tips

A fine binocular and small-telescope target. In 10x50 binoculars it appears as a small resolved clump of perhaps a dozen bright stars set in a hazy background. A 4-inch telescope at 40-60x is ideal: the cluster fills the field with 50+ stars arranged in several loose chains and clumps with distinct darker lanes crossing it. Pair the view with NGC 1545 to the south for a nice double-cluster session separate from the more famous NGC 869/884 pair. Best observed from October through March when Perseus is high in the evening sky.

History

Discovered by William Herschel on December 28, 1790. Herschel described it as 'a beautiful cluster of large stars,' noting it was easily resolved. It appears in most 19th and 20th century observing guides as a secondary Perseus target eclipsed by the fame of the nearby Double Cluster. Modern studies have refined its distance and age, confirming its membership in the young population of stars filling the Perseus arm of the Milky Way.

Fun Facts

NGC 1528 is one of several very nice Perseus clusters that get overlooked because the Double Cluster is so nearby and so spectacular. Observers who take the time to sweep the full Perseus Milky Way often come away surprised at how rich the region is beyond the famous pair. The cluster is slowly dispersing; in about another 100 million years its member stars will have drifted far enough apart that it will no longer look like a cluster at all.

Observe

1Properties

Magnitude 6.4
Angular Size 9.6′
Cl, B, vRi, cC

Position & Identifiers

RA 04h 15m 18.9s
Dec +51° 12' 41.4"
Constellation Perseus (Per)
Catalog NGC 1528
Physical size
9.7 light-years across — about 2.2× the Sun-to-Alpha-Centauri 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

Easy on Seestar S50
At 150mm under B5 skies you should resolve about 94 of 306 members.

3Visibility

Set a location in User Settings to see visibility data.

Best season Oct – Dec (peak: Nov)

4 Eyepiece View

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

NGC 1528 · 9.6′ 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 1528 295 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

}