CAPE CANAVERAL, Fla. (AP) _ Perfect weather is forecast for Saturday's launch of Stardust, a NASA spacecraft that will fly to a comet and hopefully bring back comet dust.

A Boeing Delta rocket is scheduled to blast off with Stardust at precisely 42 seconds past 4:06 p.m. NASA has only one second each day to send the spacecraft on its seven-year, 3 billion-mile journey.

``Whoever invented the term `Chamber of Commerce weather' has Florida's current weather in mind,'' Air Force weatherman Joel Tumbiolo said.

This will be NASA's first attempt to gather comet samples and bring them back to Earth.

The plan calls for Stardust to meet up with Comet Wild-2 in 2004, collecting tiny comet chips on a pop-up racket covered with a transparent glass foam called aerogel. If all goes well, the samples will return to Earth in a capsule in 2006 for scientific study.