Hercules 3rd Globular: NGC 6229

[John]

I've mentioned NGC 6229 before in observing reports.

Tonight, while waiting for the nova in Hercules to rise above the conifers, I re-visited this fainter globular cluster with my 100mm refractor, as it lies right at the top end of the constellation.

While not as striking as the other two, much better known, Hercules globular clusters M13 and M92, NGC 6229 is a very pleasing observational deep sky object and not hard to see even with 100mm of aperture. It is listed at magnitude 9.7 or thereabouts and it's stars are tightly packed so the contrast of this object is quite strong and it's shape well defined. Low magnifications show it well - I was using 37.5x this evening.

It forms a striking triangle with 2 magnitude 8 stars in the eyepiece. The tightly defined globular cluster was actually mistakenly thought to be a planetary nebula by it's discoverer William Herschel and later by Admiral Smyth. Other early observers thought it to be a comet. It was only many years later that Heinrich d'Arrest correctly identified this object as a globular cluster.

The reason for this initial uncertainty was probably because NGC 6229 is much more distant than many globular clusters being nearly 100,000 light years from Earth. That's about 4x further away than Messier 13. NGC 6229 has been classified as an outer halo cluster due to it's distance.

If you are in Hercules looking at the brighter pair of globulars, do have a look for the distant NGC 6229 as well. It's not difficult to locate and looks nice even with smaller aperture scopes

 

 

 

 

Edited June 13, 2021 by John

[Littleguy80]

I went hunting for this tonight. Found it using my 80mm refractor, which added an extra level challenge as I would normally use the 10” dob for something like this. Nice little glob which I will revisit with the dob. Thanks for highlighting this one, John!