potential relevance of "Keystone"? perhaps there is a link. Kinda crazy that 17h passes right through..
The Great Cluster in the constellation Hercules – also known as Messier 13, or M13 – is considered to be the finest globular cluster in the northern half of the heavens. It’s found in a star pattern called the Keystone – a lopsided square within the constellation Hercules – between the two brightest stars of northern spring and summer, Vega and Arcturus.
https://earthsky.org/clusters-nebulae-galaxies/m13-finest-globular-cluster-in-northern-skies