What and When Is Earth Day? When I proposed to name Earth Day, a global occasion to celebrate the wonder of life on our planet, I thought and hard about what day to choose. It must be meaningful and must be accepted by . When I came across the Vernal Equinox ( 春分 ), I immediately knew it was . What could be better the first day of spring when hearts and minds can join together with thoughts of peace and the awakening of the earth. So the first Earth Day was celebrated in San Francisco, on 22, 1970. The United Nations later accepted the day as a yearly event for people all over the world. Each year the United Nations Peace Bell rings at the moment begins.