In medieval maritime culture, Friday was considered unlucky and sailors considered it unwise to begin a voyage that day. But in 21st-century Richmond, the first Friday of the month is a glorious time to set sail on a tour through the local art world. One exhibition where you should drop your anchor during the First Fridays Art Walk on June 6 is at the group show, “Skymail,” at Gallery5. Featuring new works by Richmond artists Andrew Brehm, Luke Harman (pictured), Nicholas Crider and Spencer Erickson, the opening is followed by performances by the Hendrix-meets-NoMeansNo sound of Richmond duo Navi, the dreamy indie beats of Philadelphia’s School Dance and the electronic experimental hip-hop of the river city’s P.T. Burnem. The tsunami of artistic activity begins at 6 p.m. Free.