Sep­tem­ber 13th is my anniver­sary. 13 Engines’ Per­pet­ual Motion Machine, alt-rock from 1994, rocks. Half of the Fri­day the 13ths that fall are pay­days for me. The other half are not. But that’s okay because my wife’s pay­day is off­set from mine by a week. Her­cules, a well-known and easy-to-find con­stel­la­tion in these north­ern lat­i­tudes, con­tains the glob­u­lar clus­ter M13. …