San Antonio arts group Urban-15 will present its 23rd annual Summer Solstice dance performance  on Thursday, June 29, beneath the lighted squares of Christopher Janney’s public artwork Passing Light, a solar sculpture installed 20 years ago at the San Antonio International Airport. The free performance begins at 2 p.m., the moment when the sun reaches its highest point in the skies of the Northern Hemisphere, according to a statement from Urban-15.