Nearly 500 years after Copernicus postulated that Earth revolves around the sun, millions of Americans think otherwise, suggests a poll that found vast numbers of the nation's adults "scientifically illiterate."

Many Americans also mistakenly believe that laser beams are focused sound waves and that atoms are smaller than electrons, said Jon Miller, director of the Public Opinion Laboratory at Northern Illinois University, who conducted a nationwide survey for the National Science Foundation.In a July telephone survey, 2,041 adults 18 or older were asked about 75 questions on basic science, Miller said. The survey had a margin of error of plus or minus 3 percentage points.

Asked whether the Earth goes around the sun or the sun around the Earth, 21 percent replied incorrectly. Seven percent said they didn't know.

In the early 16th century, Polish astronomer Nicholas Copernicus laid the foundation for modern astronomy with his heliocentric theory of planetary motion in which the planets revolved around a motionless sun.

Forty-five percent correctly said it takes a year for the Earth to orbit the sun, but 17 percent said one day, 2 percent said one month and 9 percent didn't know.

"The results show that on very basic ideas, vast numbers of Americans are scientifically illiterate," Miller said Sunday. "It's a fairly dire situation."

The results of the survey haven't been fully tabulated yet, but it appears that 93 percent to 95 percent would have to be considered scientifically illiterate, lacking fundamental knowledge of scientific vocabulary, methodology and an understanding of science's impact on the world, said Miller. The group's 1985 survey found a 95 percent illiteracy rate.

The results indicate many Americans have little idea of what presidential candidates are talking about when they list key issues such as the Strategic Defense Initiative, acid rain, the greenhouse effect and the space race, he said.

Leon Lederman, who last week was named co-winner of the 1988 Nobel Prize for physics and is director of the Fermi National Accelerator Laboratory in Batavia, called the latest findings "pretty devastating."

"How you can preserve democracy when the world is increasingly more complex scientifically and technologically, and people are increasingly more ignorant of the issues?" he asked.

On other questions, the survey found that 43 percent said correctly that electrons, which are components of atoms, are smaller than atoms; 20 percent thought they were larger and 37 percent had no idea.