Globular clusters are amongst the finest objects to observe in the night sky. The brightest are dazzling balls of stars, but their origins are wrapped in mystery. These objects are as old as our galaxy and likely to have formed or be captured eons ago. These objects truly are ‘ancient light’

There are relatively few globular clusters observable around our galaxy (about 158), but there are many around neighbouring galaxies and in galaxies far away.

Many thanks to Paul Leyland who has prepared two challenges for globular clusters around our galaxy (the full and restricted challenges), and one on extra-galactic globular clusters which is still under preparation.

The GC Marathons: Three 21st Century Challenges.
Part I — Galactic Globular Clusters