Caldwell 102 — Open Cluster in Carina
IC 2602
About Southern Pleiades
Description
The Southern Pleiades (IC 2602) is one of the brightest open clusters in the sky, located about 479 light-years away in Carina. At magnitude 1.9 it is easily visible to the naked eye, spanning over a degree and dominated by the blue-white star Theta Carinae.
Observing Tips
Best in binoculars — too large for most telescope fields. The cluster is immediately obvious to the naked eye as a bright knot in the Milky Way. About 60 stars are visible in binoculars around the brilliant Theta Carinae. Best from southern latitudes in late winter and spring.
History
Known since antiquity to southern hemisphere observers. Nicolas Louis de Lacaille cataloged it in 1751. It earned its nickname from its visual similarity to the Pleiades (M45), though it is younger and more spread out.
Fun Facts
At only 30 million years old, the Southern Pleiades is even younger than its northern namesake. Theta Carinae, the cluster's brightest star, is a spectroscopic binary with a combined luminosity of about 22,000 Suns.
Observe
1Properties
Position & Identifiers
2How easy to spot?
| 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 |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
3Visibility
Set a location in User Settings to see visibility data.
4
Eyepiece View
5
Best Magnification
6Where this cluster sits in time
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.
Each point is a Gaia-DR3 member. Colour encodes spectral type; size reflects membership probability.
Discover
8
Light Travel Time Machine
9
Relativistic Travel
Community Photos (1)
Credit: Tel Lekatsas. License: CC BY 2.0. (Wikimedia Commons)
Skybred Mar 2, 2026
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.
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