Set for launch in February 1999, Stardust will be the first U.S. mission dedicated solely to a comet and the first robotic return of extraterrestrial material from outside the orbit of the Moon. Its primary goal is to collect comet dust and volatile samples during a planned close encounter with comet Wild 2 in January of 2004. Additionally, the Stardust spacecraft will also bring back samples of interstellar dust including the recently discovered dust streaming into the solar system from the direction of Sagittarius.
These materials consist of ancient pre-solar interstellar grains and nebular condensates including remnants left over from the formation of the solar system. Their analysis is expected to yield important insights into the evolution of the sun and planets and possibly into the origin of life itself.
The spacecraft will make three loops around the sun. On the second loop, the trajectory of the spacecraft will intersect that of Wild 2. During encounter the spacecraft will send back pictures of Wild 2, counts of comet particles striking the spacecraft, and real-time analyses of the compositions of the particles and volatiles. The capture mechanism for the returned samples will use a unique substance called aerogel attached to panels on the spacecraft to soft-catch and preserve the cometary materials. These will be dropped off in a reentry capsule that will parachute to Earth in 2006.
STARDUST is a collaborative effort between NASA, university and industry partners. The principal investigator is Donald E. Brownlee of the University of Washington, well known for his discovery of cosmic particles in the stratosphere known as Brownlee Particles. Peter Tsou of the Jet Propulsion Lab, innovator in aerogel technology and maker of aerogel, serves as Deputy Investigator. The contractor for the STARDUST spacecraft is Lockheed Martin Astronautics. The Jet Propulsion Lab will provide an experienced project management team, led by Kenneth L. Atkins, an early leader in comet missions. In addition, JPL will provide the optical navigation camera, and the Max Planck Institute (MPI) of Germany will provide the real-time dust composition analyzer for the spacecraft.
STARDUST is the fourth NASA Discovery mission to be chosen and following on the heels of Mars Pathfinder, the Near Earth Asteroid Rendezvous (NEAR) mission, and the Lunar Prospector mission. The goal of NASA's Discovery Program is to launch many, smaller missions that perform focused science with fast development times, cost less than $150 (FY92$) million to build, and are joint efforts with industry, small businesses, and universities.