The Stardust spacecraft, en route to collect comet dust and return it to Earth, will fly by a small asteroid next month and use the opportunity to test equipment and procedures, NASA officials said this week. The asteroid, discovered in 1942 and later named Annefrank, is about 2.5 miles (4 kilometers) in diameter.

"This is an engineering test," said Thomas Duxbury, Stardust project manager at NASA's Jet Propulsion Laboratory. "We have no science goals or science expectations at Annefrank. It's an opportunity to try key procedures for the first time before we get to comet Wild- 2. We may identify problems that we can address before we reach our primary target."

Stardust will pass within about 1,900 miles (3,000 kilometers) of the rock and will automatically snap a picture. The great distance, however, will make it impossible to see any surface detail, scientists said. Stardust is to hook up with Wild-2 in 2004 and bring samples back in 2006.How are asteroids named?