Caldwell 81 — Globular Cluster in Ara
NGC 6352
About C81
Description
NGC 6352 is a globular cluster in Ara, about 18,300 light-years away. It is a relatively sparse, low-concentration cluster spanning about 7 arcminutes with an integrated magnitude of 8.2.
Observing Tips
Visible as a faint, round glow in a 6-inch telescope. An 8-inch scope begins to resolve the outer stars. Not as spectacular as nearby southern globulars but a pleasant target. Best in summer from southern locations.
History
Discovered by James Dunlop on June 14, 1826 from Australia. It is one of the metal-rich globular clusters in the inner halo of the Milky Way.
Fun Facts
NGC 6352 has a relatively high metal content for a globular cluster, placing it among the younger generation of globulars that formed after the galaxy had been enriched by earlier generations of supernovae.
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
6Metallicity
[Fe/H] = -0.64 — these stars formed from gas about 4.4× poorer in iron than the Sun.
7Concentration class
Shapley-Sawyer class VII — diffuse profile with a loose outer envelope.
Explore
8
Classification Decoder
Discover
9
Light Travel Time Machine
10
Relativistic Travel
Community Photos (1)
Credit: NASA - Hubble Space Telescope. License: Public domain. (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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