4:16 On April 22, 2021, Earth Day will celebrate its 51st year, but environmental pioneers and poets have been writing about the need to care for our planet much longer. A new audio production called "Voices of the Earth" presents thoughts about the environment from across the ages. Rush Rehm, a theater and classics professor at Stanford University, worked with co-creator Charles Junkerman on this production for the Stanford Repertory Theater. Rehm said the play features staged readings by students and professionals. “We decided that it wouldn’t be just about contemporary thoughts on the environment but to go back to ancient Greek and Sanskrit and to earlier societies,” Rehm said.