Astronomy Adventure – Messier 15 by eeggert · September 20, 2018 Messier 15 is a globular cluster in the constellation Pegasus. It is among the oldest globular clusters, around 12 billion years old. Technical details: Scope: Starblast 4.5; tracking on Magnification: ~30x Camera: iPhone6 using NightCap Pro; ISO 8000; Share