In October, 1985, the largest and most diverse group of astronauts and cosmonauts in history assembled at the historic ninth century Abbey de Cernay in Cernay, France. Twenty-five space fliers from thirteen countries convened to form the Association of Space Explorers, the world's first international society of flown astronauts and cosmonauts. The First Planetary Congress was co-chaired by US astronaut Rusty Schweickart and Soviet cosmonaut Alexei Leonov.

The astronauts and cosmonauts met together to explore their shared vision of the planet, derived from their experiences in space, which united them in a way that transcended their cultural and political differences. As Saudi Arabian flier Sultan bin Salman bin Abdulaziz remarked in the Opening Ceremony:

"The first day or so we all pointed to our countries.The third or fourth day we were pointing to our continents. By the fifth day, we were aware of only one Earth."

All of the fliers who attended acknowledged that they had been substantially affected during their flights by a heightened sense of awareness of the beauty and fragility of our home planet, the Earth. During the Congress, this sentiment was reflected by Alexei Leonov:

"Astronauts and cosmonauts are the handful of people who have had the good fortune to see our Earth from afar and to realize how tiny and fragile it really is. We hope that all the people of the earth can understand this, and treat the Earth as the home in which they are born, the home in which they live, and the home where their children and grandchildren will live after them."