HOW EARTH DAY WORKS

History of the Equinox Earth Day

The equinoctial Earth Day is celebrated on the March equinox (around March 20) to mark the precise moment of astronomical mid-spring in the Northern Hemisphere, and of astronomical mid-autumn in the Southern Hemisphere. An equinox in astronomy is that moment in time (not a whole day) when the center of the Sun can be observed to be directly "above" the Earth's equator, occurring around March 20 and September 23 each year. In most cultures, the equinoxes and solstices are considered to start or separate the seasons.

John McConnell first introduced the idea of a global holiday called "Earth Day" at the 1969 UNESCO Conference on the Environment. The first Earth Day proclamation was issued by San Francisco Mayor Joseph Alioto on March 21, 1970. Celebrations were held in various cities, such as San Francisco and in Davis, California with a multi-day street party. UN Secretary-General U Thant supported McConnell's global initiative to celebrate this annual event; and on February 26, 1971, he signed a proclamation to that effect, saying:

May there be only peaceful and cheerful Earth Days to come for our beautiful Spaceship Earth as it continues to spin and circle in frigid space with its warm and fragile cargo of animate life.^[United Nations secretary-general Kurt Waldheim observed Earth Day with similar ceremonies on the March equinox in 1972, and the United Nations Earth Day ceremony has continued each year since on the day of the March equinox (the United Nations also works with organizers of the April 22 global event). Margaret Mead added her support for the equinox Earth Day, and in 1978 declared:

"Earth Day is the first holy day which transcends all national borders, yet preserves all geographical integrities, spans mountains and oceans and time belts, and yet brings people all over the world into one resonating accord, is devoted to the preservation of the harmony in nature and yet draws upon the triumphs of technology, the measurement of time, and instantaneous communication through space.

Earth Day draws on astronomical phenomena in a new way – which is also the most ancient way – by using the vernal Equinox, the time when the Sun crosses the equator making the length of night and day equal in all parts of the Earth. To this point in the annual calendar, EARTH DAY attaches no local or divisive set of symbols, no statement of the truth or superiority of one way of life over another. But the selection of the March Equinox makes planetary observance of a shared event possible, and a flag which shows the Earth, as seen from space, appropriate."

At the moment of the equinox, it is traditional to observe Earth Day by ringing the Japanese Peace Bell, which was donated by Japan to the United Nations. Over the years, celebrations have occurred in various places worldwide at the same time as the UN celebration. On March 20, 2008, in addition to the ceremony at the United Nations, ceremonies were held in New Zealand, and bells were sounded in California, Vienna, Paris, Lithuania, Tokyo and many other locations. The equinox Earth Day at the UN is organized by the Earth Society Foundation.