Messier 13 (M 13)

Introduction | Map | Sketch | My Own Observations | References

On this page I collect my observations of the globular star cluster M 13 in the constallation Hercules.



The globular star cluster M 13 in the Hercules constellation is probably the largest globular cluster in the northern sky. It is located on the right edge of the Keystone asterism, which is the most prominent part of the constellation Hercules and forms a trapezoid. M 13 is not quite round and, depending on the author, 8 'or 15' in size. I was able to see the bright nucleus well, but I was not able to resolve single stars. Overall, this cluster is an easy-to-find object, even with binoculars (for example, on Oct. 31, 2016 in Mühlhausen / Kraichgau - but only faintly), at least once you have found the Keystone asterism.

Size: 8' / 15' (Stoyan/Karkoschka)
Distance: 24,000 light years (Stoyan)
Rating: **** (Stoyan)



M 13 is located at the right edge of the Keystone asterism (1/3 from the top) and is relatively easy to find once you have found the Keystone trapezoid.



The sketch by Michael Vlasov ( provides a rough impression of what I observed in Summer/Autumn 2016 (my impression was much fainter and smaller than the sketch):

Sketch of the M 13 globular star cluster by Michael Vlasov (Copyright © Michael Vlasov 2016) - presented with the author's permission


My Own Observations

Observations Summer to Autumn 2016

Observations February/March 2017

Observations May 2017

Observations September 2017

Observations October/November 2017



On this Site