Johnson Space Center cleanroom Certified (07-99)

View 11 minute educational video on cleanroom technology.

Teacher Guide Student Activity

Teachers, use these instructional materials to fully engage your students. Adobe Acrobat Reader required (see below).

To read print-optimized files, download Adobe Acrobat Reader.

An important milestone for future outreach work was attained in mid-July 1999. The Genesis spacecraft will carry a science canister containing pure materials in which to collect solar wind particles and return its valuable cargo to Earth for analysis. The cleanroom where the science canister was assembled at the Johnson Space Center (JSC) in Houston, Texas, was certified in July as functioning at the high purity level that it was designed for.

Cleanroom facility floor plan. Courtesy: Johnson Space Center

For the array assembly process and eventual archiving of the returned solar wind samples, JSC built a cleanroom facility dedicated to the Genesis mission. The new cleanroom was designed and is supervised by Dr. Eileen Stansbery, contamination control lead for the Genesis mission at JSC.

Stansbery states that the primary objective of this cleanroom is to "protect [the Genesis spacecraft's] collector surfaces from contamination before and after" they are exposed to solar wind in space. "To do that implies a non-contaminated installation and a clean payload interior." Additionally, some payload components need to be cleaned individually before they are installed in the canister.

Cleanrooms are used in hospitals, in the production of electronic equipment, and for the curation of samples. Despite the name, cleanrooms are never totally contaminant-free. They are classified from a rating of 100,000 down to 1 by the amount of contamination present during operation. Class 1 cleanrooms are the most sanitary. There can be no more than one dust particle larger than 1 micron across per cubic foot of air moving through it in one minute.

The average room in a house has approximately 350,000 dust particles of that size moving through a cubic foot of air in a minute; thus it is class 350,000. Hospital operating rooms are typically class 10,000 to class 1,000. The JSC cleanroom used for the Genesis assembly is certified as class 10. Collector materials must be as pure as possible when sent into space. In 2004, when the solar wind samples are returned to Earth, scientists will know that any ions embedded in the wafers are from the solar wind.

Technician in "bunny suit" examines collector wafer inside JSC cleanroom. Courtesy: Johnson Space Center

Technicians enter the JSC cleanroom facility through a dressing area where they don protective clothing called "bunny suits." Rather than protecting the technicians from their environment, these suits protect the cleanroom from the technicians' bodies, including skin flakes and other contaminants.

The cleanroom has floors containing many small holes. Air is constantly moving down from the ceiling, sweeping air-borne contaminants through the floor and into special cleaner-traps to remove particulate contaminants. The cleaned air moves up through the walls of the room to be reintroduced through the ceiling.

Engineering model of Genesis science canister. Courtesy: Jet Propulsion Laboratory

To test the cleanroom and procedures for working in it, Stansbery's team recently completed a dress rehearsal for the processing of the complete science canister using an engineering model. This is a mock-up of the container for the collector arrays and the concentrator, components that will hold samples of solar wind until they are returned to Earth in 2003. This particular engineering model has been used to test other features of the Genesis spacecraft as well.Don Sevilla, payload team leader from the Jet Propulsion Laboratory (JPL), which directs the Genesis mission, was at JSC to watch the canister disassembly and re-assembly procedure.

Sevilla was most interested in the cleaning process, and the process for verifying the cleanliness of the final product. He commented on the "good team spirit" between staff from JPL and JSC working together on the project. Staff members at JSC were very impressed by the new cleanroom's purity, and by how clean it remained during the mock procedure.

Stansbery is excited about the opportunity to participate in the Genesis mission. "The public will own the [Genesis] solar wind samples," she says. "In essence, they will be a national resource."