Once placed in a "halo orbit" between Earth and the Sun, the probe will sunbathe for some 26 months, quietly snagging material spit out from old Sol. Then, with its bounty of solar particles in tow, Genesis hauls back the goods for Earth reentry and a midair recovery over the Utah desert in September 2004.

The $260 million Genesis mission is the latest in the line of Discovery probes like the Near Earth Asteroid Rendezvous (NEAR) spacecraft, the Stardust comet mission, and Lunar Prospector all belonging to the econo-class stable of faster, better, cheaper space explorers.

Genesis is the first NASA sample-return mission since Apollo astronauts brought back lunar materials in 1969 through 1972, said Nick Smith, chief system engineer for the spacecrafts flight system.

"Genesis is truly a planetary spacecraft. But its very unusual compared to other spacecraft because its not leaving the Earths gravity well," Smith told SPACE.com. "We are rewriting the text books," he said.

Smith worked with Don Burnett, principal investigator of the Genesis mission at the California Institute of Technology (Caltech) in Pasadena, California, in the first phase of spacecraft design. "I still have those early sketches. It hasnt turned out too differently," he said.

Once lofted into space, the probe is to be stationed at the Sun-Earth libration (L-1) point, where the gravitational pulls of the Sun and Earth are balanced. At the L-1 point, Genesis is some 0.93 million miles (1.5 million kilometers) from Earth, approximately 1 percent of the Earth-Sun distance.

The spacecraft will enter a halo orbit about the L-1 point, Smith said, outside the influence of Earths magnetic field. "Its a good place to go," Smith said.

While loitering around this unreal real estate, Genesis will expose sets of ultra-pure silicon wafers that will snag pure solar wind material.

Our Sun is a holdout. That is, it contains well over 99 percent of all the material in the solar system. Solar wind particles are similar to material from which the planets formed, at a time thought to be some 4.6 billion years ago.

Although the suns interior has been modified by nuclear reactions, the outer layers of our star are thought to be composed of the same matter as the original solar nebula.

By having Genesis gather particles flung out from the Sun and then haul that material back to Earth, scientists can use high-tech tools to compare the Suns makeup with data known about moons, planets, comets and asteroids.

By collecting pieces of the Sun, another piece of the puzzle regarding planetary origins may be locked in place.

To catch solar wind ions and atoms, Genesis exposes collector arrays comprised of hexagonal wafers made of very pure materials, such as silicon, germanium -- even diamond-coated silicon.