Caldwell 47 — Globular Cluster in Delphinus
NGC 6934
About C47
Description
NGC 6934 is a globular cluster in Delphinus, about 50,000 light-years away. It is a moderately concentrated cluster spanning about 5.9 arcminutes with an integrated magnitude of 8.9.
Observing Tips
Visible as a small, fuzzy ball in a 4-inch telescope. An 8-inch scope begins to resolve the outer edges into individual stars at 150x+. Located in Delphinus, best observed in summer and autumn evenings.
History
Discovered by William Herschel on September 24, 1785. It is one of two Caldwell globular clusters in the small constellation Delphinus (along with C42).
Fun Facts
NGC 6934 contains a relatively high number of RR Lyrae variable stars, which are used as standard candles for measuring distances in astronomy.
Observe
1Properties
Position & Identifiers
2How easy to spot?
| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Easy | Medium+ | Medium+ |
| 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
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Relativistic Travel
Community Photos (1)
Credit: en:NASA, en:STScI, en:WikiSky. 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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