When the Soviet Union launched Cosmos 1941 this spring, it added one productive satellite in orbit and 28 pieces of junk.

Every rocket that slices through the atmosphere to the void beyond adds to the litter, which totals 7,110 pieces, according to the U.S. Space Command in Colorado, which tracks each chunk. The United States and Soviet Union are the principal contributors, with 3,148 and 3,246 pieces, respectively.The trash has included paint flakes, screws and even the thermal glove that floated out of Gemini 4 in 1965 on America's first space walk.

Space station planners "are faced with a considerable design problem," because of the junk, says Don Kessler, project scientist for debris studies at NASA's Johnson Space Center. They've added 2,000 pounds of shielding to each of the six modules that will be occupied by astronauts.

"A 3-millimeter particle has as much kinetic energy as a bowling ball going 60 miles an hour," Kessler says.