…continuedClusters of Clusters: Globular Pairings
In and Around the Teapot
There are perhaps only 1,000 light-years separating this pair of clusters they not only appear close together in the sky; they may actually be close neighbors in space. It has been said that the sky of a planet located inside a globular cluster would be filled with so many
Finishing off our tour, we come to one of the night sky's true showpieces. For most Northern Hemisphere observers, M22 is the most spectacular globular visible, being both larger and brighter than the better-known M13 little wonder, considering it is only half as far away! This glorious cluster is easily resolved. Even my trusty 2.4-inch refractor showed a grainy texture at 117x during superb seeing. Moderate apertures produce unforgettable views of swarms of stars arrayed across the elliptically shaped cluster's glowing core. At 174x my 16-inch Meade Newtonian revealed two chevron-shaped dark lanes pointing south. Does anyone else see these patterns?
M22 is accompanied by 9th-magnitude NGC 6642, 1.1° to the west-northwest. Given the spectacular appearance of M22, it's little wonder that NGC 6642 receives so little attention. Halifax Royal Astronomical Society of Canada member Daryl Dewolfe observed this cluster with his 5.7-inch Ceravolo Maksutov-Newtonian, noting, "At 83x there appeared to be a faint chain of stars leading to the globular."