Caldwell 58 — Open Cluster in Canis Major
NGC 2360
About C58
Description
NGC 2360 is an open cluster in Canis Major, about 3,700 light-years away. It is a rich, well-concentrated cluster containing about 80 stars within 13 arcminutes, with an age of roughly 2.2 billion years.
Observing Tips
A fine cluster in a 4-inch telescope at medium power. The background Milky Way star field adds to the view. Many of the cluster stars are similar in brightness, giving it an even, grainy appearance. Best in winter evenings.
History
Discovered by Caroline Herschel on February 26, 1783. It is one of the notable discoveries by William Herschel's sister, a pioneering astronomer in her own right.
Fun Facts
Caroline Herschel discovered this cluster using a small refractor while conducting her own independent sky surveys. She discovered 8 comets and several nebulae and clusters during her career.
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.
Explore
8
Classification Decoder
Discover
9
Light Travel Time Machine
10
Relativistic Travel
Community Photos (1)
Credit: Sloan Digital Sky Survey. License: CC BY 4.0. (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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