M107 is one of more than 20 bright globular clusters in Ophiuchus, seven of which belong to the Messier catalog. You'll find this 7.8 magnitude cluster 2.7 degrees southwest of 2nd magnitude Zeta (13) Ophiuchi. At 129X in my 10-inch Newtonian, M107 presents an 8' diameter form with 11th and 12th magnitude stars defining its outer boundaries. The cluster displays three section: a 2' diameter central core, a somewhat brighter adjacent layer extending 4' across and an outer envelope reaching 8' across. A row of four 13th and 14th magnitude stars are visible in the northern half of the cluster.