NASA's Genesis spacecraft that holds a collection of solar wind particles performed a trajectory-trimming maneuver over the weekend. The craft is right on track to reach its intended drop zone on September 8, the Air Force's Utah Test and Training Range, southwest of Salt Lake City.

The Genesis maneuver on August 29 was very precise, said Joseph Vellinga, Genesis Program Manager for Lockheed Martin Space Systems Company. "It was a very efficient operation," he told SPACE.com shortly after the spacecraft adjusted its path toward Earth.

A follow-on trajectory maneuver is planned for September 6, at 52 hours prior to Genesis plowing into Earth's atmosphere en route to its airborne capture over Utah desert.

Trajectory tweaking

Following the spacecraft's weekend trajectory tweaking, tracking experts are now determining the preciseness of the maneuver, Vellinga said. "It looks very accurate."

Genesis recovery teams are set to conduct a high-fidelity dress rehearsal next weekend, practicing for the real sky show on September 8. That run-through will involve trajectory and navigation experts, helicopters, a simulated capsule under parafoil-glide, and a shakeout of procedures and ground personnel duties.

Next week, the Genesis sample return capsule will be snagged in midair by helicopter. This in-the-air retrieval technique should safeguard delicate space-soaked wafers that snared particles of the Sun from high-g loads due to a rough and tumble ground landing.

First material collected beyond the Moon

The Genesis capsule is carrying NASA's first return samples beyond Earth since the final Apollo lunar moonwalk mission in 1972, and the first material collected beyond the Moon.

It will enter Earth's atmosphere next week on Wednesday, at 9:55 A.M. local Mountain Time. Two minutes and seven seconds after atmospheric entry, while still flying supersonically, the capsule will deploy a drogue parachute at 108,000 feet (33 kilometers) altitude. Six minutes after that, the main parachute, a parafoil, will deploy 20,000 feet (6.1 kilometers) up.

Waiting below will be two helicopters and their flight crews ready to snare the Genesis capsule. The helicopter that does achieve capture will airlift the sample canister to a clean room at the Michael Army Air Field at the U.S. Army Dugway Proving Ground.

The invaluable samples will then be trucked to a special laboratory at NASA's Johnson Space Center in Houston, Texas where they will be preserved and cataloged under ultra-pure cleanroom conditions and made available to the world scientific community for detailed study.