Cleanroom planned for Mars samples
Houston — Scientists at National Aeronautics and Space Administration`s (NASA) Johnson Space Center are just beginning the long process of deciding what they need for storing and studying Mars samples that will be brought back to Earth by the year 2005. Whatever they decide, contamination control is a paramount issue from two critical standpoints: protecting the Earth and protecting the samples. “It`s not too soon to begin creating a specifications list,” says Judith Allton, a principal scientist with Lockheed Martin in Houston supporting the Solar System Exploration Division at Johnson Space Center (JSC). “The maze of government regulations, environmental concerns, and international political considerations accompanying the process is coupled with some unique technical requirements.”
John Rummel, NASA`s planetary protection officer, explains that creating a specifications list is difficult when it is not known exactly what will be brought back to Earth. Scientists have a good idea because asteroids believed to be from Mars have hit Earth, and these have been analyzed. But pristine samples from Mars that have not been in contact with or contaminated by Earth require special handling.
“We`ll probably have to build something like a Level 3 or 4 facility,” Rummel says, referring to the type of Bio-Safety facility the Centers for Disease Control (CDC) maintains in Atlanta, GA, for studying deadly viruses. “We don`t want the sample contaminated nor do we want the Earth contaminated by the sample. So this would call for positive and negatively pressurized corridors and rooms so there is no leak in and no leak out. How to isolate the samples perfectly and still be able to work with them will be a real challenge.”
Such a facility would be a marriage of the technologies now used in building pharmaceutical or semiconductor industry cleanrooms, Rummel says. The facility would also have to be organically clean. Alternatives must be found for some traditional cleanroom products such as swabs, cleaners and wipers made from organic materials.
Scientists searching for evidence of past or present life need to be certain that if they discover something, it`s not just a few organic fibers from a cotton cleanroom swab or a drop of sweat from a worker. This calls for a facility more advanced than the Class 10,000 laboratory that houses some 842 pounds of moon rocks from the Apollo 1969 to 1972 missions. The Lunar Sample Laboratory at JSC is not designed as a quarantine facility, since it was built after NASA determined that the moon rocks posed no health danger. But in the case of the Mars samples, the initial facility should be considered an entirely safe facility where absolutely no contact between the samples and Earth can take place, Allton explains.
She says it is not known yet if money will be available to build a new facility, and that NASA has several options to consider. A facility comparable to the Lunar Sample Facility would cost upwards of $125 million today, she says. However, plans must be in place prior to launch.
NASA will be considering all its options carefully. Allton says it`s possible that the Lunar Sample Facility at JSC could be modified to include an area for the Mars samples. She says some possibilities include upgrading cleanroom facilities maintained at Fort Detrick, Frederick, MD, where the Army`s Medical, Research and Development Command is headquartered or remodeling part of the facilities at the White Sands Missile Range in Alamogordo, NM.
Dr. Carl Agee, chief scientist for Astromaterials at JSC began addressing this topic in August when he was brought on board to assist in analysis of all of the issues involved in Mars sample curation — the first step toward deciding exactly what kind of cleanroom is needed.
Judy Keller is a freelance writer in Milford, NH.