They came, shot, and printed; A Day in the Life of Australia, edited by Rick Smolan and Andy Park. New York: Harry N. Abrams Inc. 288 pp. $40.

The idea was simple: invite 100 of the world's best photojournalists to Australia to record life on the island continent, as it took place on March 6, 1981. Loaded with film and cameras, the photographers would freeze a ''moment in time.'' Within Australia, the filming became an event itself.

The photographers came, shot, and handed in their pictures. Their 24 hours of work resulted in this book, which was first published in Australia in 1981, but has recently been released in the United States.

The project, ambitious in its simplicity, has tried somewhat successfully to capture a nation on film. Sometimes the photographers shot family scenes, at other times Aussies at work or play. Some of the photos are outstanding. Not all. For example, each photographer was asked to shoot pictures of the owners of small businesses standing in front of their establishments. Unfortunately, there is nothing remarkable about these pictures.

One innovation the editors should be commended for is the inclusion of small maps of the continent that pinpoint where each picture was taken.

The book goes beyond the strictly coffeetable genre. It keeps coming back to the people - miners taking a break at Mount Isa in Queensland; Melbourne school girls in straw hats and school dresses; inmates in Adelaide Gaol in South Australia; aborgines on one side of a road outside Darwin, drinking and socializing, while whites do the same on the opposite side.

Certainly there are some areas missing in this photo record. With over three-quarters of the Australian population located in the cities, there are too many photos from rural areas. And, since Australians spend so much of their time on or near the beaches, water shots are lacking as well. But, all in all, the book successfully portrays a day of life in Australia.