HOUSTON -- Walter Cronkite, the American television broadcaster whose coverage of the Apollo moon program inspired a generation amid the turbulent 1960s, assured those gathered here for the World Space Congress that they are living in an age not unlike the dawn of the Renaissance.

The new era began on July 20, 1969 when the first human beings landed on the moon and "escaped our Earthly environment," Cronkite said in the inaugural address Monday to the once-a-decade gathering of space scientists, engineers, business leaders and visionaries.

"Young people five hundred years from now, living out in space, living perhaps on a planet, certainly living in space cities erected out in spaceThats the date they will remember about the 20^th Century," Cronkite said.

Cronkite and other speakers at the inaugural ceremony attempted to strike an upbeat theme at a time when space agencies around the world are facing budget shortfalls, and scientists are under increasing pressure to justify their programs.

"Its frequently stated that space has lost its romantic appeal," said Brazils Marcio Nogueira Barbosa, president of the International Astronautical Federation. "Its up to the space community broadly represented in this Congress to find the again the role of man over a brilliant future, full of enthusiasm," he said.

Barbosa, who is also the deputy director general of the United Nations Educational, Scientific and Cultural Organization, urged space leaders to apply space technology and science to "sustainable development and welfare" around the globe. The benefits of space acitivities "have not so far reached the major parts of humanity," he said.

American Jim Albaugh, president and CEO of Boeing Integrated Defense Systems, urged leaders to do more than envision a future rich in space technology. It will be necessary, he said, "to apply the knowledge and political will to make it happen," he said.

Pioneers, he added, need "resources behind them."