We normally think of pollution and waste as an earthly problem, but recent research has shown that space is quickly filling up with trash as well. Even astronauts create trash, and figuring out what to do with it in the cramped confines of a space ship is a problem NASA is eager to tackle.
Just like here on Earth, astronauts living in a space shuttle generate trash — from plastic water bottles and foil drink pouches to old clothing. The difference is that there are no garbage collectors or recycling centers in space. Researchers from NASA’s Ames Research Center in California recently developed a method for upcycling this waste into compact discs that can be stored aboard spacecraft safely or even used for radiation shielding during a deep-space mission.
Although plastic is made from toxic materials and takes centuries to degrade when disposed of in a landfill, NASA researchers say it could be the ideal material to make shields that insulate a crew against deep space radiation. Possible areas for increased radiation shielding include astronauts’ sleeping quarters or perhaps a small area in the spacecraft that would be built up to serve as a storm shelter to protect crews from solar flare effects.
The circular tile, or “trash disc” pictured above was produced at the Ames Research Center, where engineers developed and built a compactor that melts trash but doesn’t incinerate it. After compaction, a day’s worth of garbage becomes an 8-inch diameter tile about half an inch thick. Plastic water bottles, clothing scraps, duct tape and foil drink pouches are left patched together in a single tile along with an amalgam of other materials left from a day of living in space.
“Handling trash is an important consideration for NASA mission planners and astronauts for several reasons,” states NASA. “First, no one wants a cramped spacecraft to become overrun with garbage. Second, resources will be extremely limited for a crew that will be expected to live in space for up to two years, the time it would take for a Mars mission. Crews cannot simply jettison trash as they go through space because it could land on — and possible contaminate — a planet or moon. NASA policy dictates avoiding contaminating other worlds.”
Before the technique can be tested in space, researchers must determine whether compaction leaves any dangerous microbes. “They are achieving sterilization for the most part,” said Mary Hummerick, a Qinetiq North America microbiologist at Kennedy working on the project. , explaining that test strips containing bacterial spores are embedded in the tiles to see if the heating and compaction process is effective in killing bacteria. “What we don’t know is, can a few possible surviving bacteria go inert and then grow back.”