From the "JPL Universe"
August 22, 1997

The Stardust mission has successfully passed its critical design review, which means the spacecraft is right on track for its launch as the next Discovery mission in February 1999. Stardust will collect comet dust and interstellar particles for return to Earth.

"This approval signals that we've finished designing those mission-unique elements that needed to be designed," said Stardust Project Manager Dr. Kenneth Atkins. "Our main task now is to fabricate, build and test the flight and ground systems."

As the third NASA Discovery mission after Near Earth Asteroid Rendezvous (NEAR) and Mars Pathfinder, Stardust must adhere to the "faster, better, cheaper" credo. Atkins explained, "We've tried to use as much inherited, proven and low cost subsystem elements as possible. However, we needed to design some unique elements, such as the means for capturing comet dust and interstellar particles, something that has never been done before."

Stardust will loop twice around the Sun and collect interstellar dust particles before it flies past Comet Wild 2 in 2004. The spacecraft will gather dust particles spewed from the comet's coma (near the nucleus in the head) and return them to Earth in 2006, making it the first-ever mission to return material from a solar system object beyond the moon.

The captured particles will be embedded safely in aerogel, a sponge-like silica gel which has empty space as 99 percent of its volume. Aerogel has played a vital role in the Mars Pathfinder mission by providing thermal insulation for the rover Sojourner as it meanders around the Martian landing site.

"In a sense, Stardust, like the current Mars mission, is also a 'pathfinder,'" Atkins said. "While Mars Pathfinder has proven a low-cost means to land a spacecraft on other planets, Stardust will pioneer a low-cost technique for returning samples of extra-terrestrial materials to Earth."

"This represents a new approach to retrieving materials from the solar system and beyond and returning them to the worldwide science community," Atkins explained. "The materials can be studied in the most advanced laboratories and universities."

The precious Stardust cargo will be stored in a capsule designed to separate from the spacecraft's main body and descend into Earth's atmosphere, landing in Utah. The main spacecraft will continue in orbit around the Sun indefinitely.

Scientists are anxious to study comet dust because comets, rich in organic compounds, are the most primitive bodies in the solar system and may teach us more about the birth of the planets and the formation of life.

NASA has already spent about $60 million and will spend an additional $68 million on spacecraft development before the February 1999 launch date. The seven-year flight operations to the comet and back will add another $37 million. The solar- powered Stardust will be launched on the low-cost Delta II Rocket provided by McDonnell-Douglas, keeping the project solidly in the Discovery class of missions.

Stardust Principal Investigator Dr. Don Brownlee of the University of Washington leads the team collaborating on Stardust. The spacecraft and sample return capsule are being built by Lockheed Martin Astronautics in Denver.