An experiment that’s on its way to the International Space Station focuses on a subject that’s as common as dirt, but could be the key to growing crops in space.
The NASA-funded experiment — known as Dynamics of Microbiomes in Space, or DynaMoS — is being conducted by researchers at the Pacific Northwest National Laboratory. DynaMoS makes use soil and bacteria that were collected at a Washington State University field site in Prosser, Wash.
“Soil microbes are the hidden players of the life support system on planet Earth,” PNNL chief scientist Janet Jansson, the principal investigator for the DynaMoS experiment, explained during a pre-launch news briefing. The bacteria work to break down organic matter and make nutrients available for growing plants.
Space missions could extend the microbes’ reach beyond our home planet.
“Soil microbes can help to make conditions on the lunar surface and Mars more favorable for plant growth,” Jansson said. “They can also be used to help grow crops on space stations and during long-term spaceflight.”
To figure out how the space environment affects the work done by soil microbes, scientists packed 52 test tubes containing soil laden with eight types of bacteria aboard a robotic SpaceX Dragon cargo capsule that’s bound for the space station. Another 52 tubes are being kept in a lab for comparison.
The shipment was originally scheduled for liftoff from NASA’s Kennedy Space Center in June. But that attempt was called off when engineers detected elevated readings of hydrazine propellant while the Dragon was being fueled up.
Today’s launch, in contrast, went off without a hitch. Minutes after SpaceX’s Falcon 9 rocket blasted off, the first-stage booster landed itself on a drone ship stationed in the Atlantic Ocean, while the Dragon continued its robotic trip to orbit.
The schedule calls for the Dragon to rendezvous with the space station on Saturday, delivering about 5,800 pounds of supplies and experiments — including DynaMoS.
PNNL’s researchers plan to monitor how well the bacteria in the soil samples break down a substance known as chitin, which is found in the exoskeletons of insects and the cell walls of fungi. Chitin is the world’s second most abundant type of polysaccharide, after cellulose, and serves as a common food source for microbes.
When microbes consume chitin, they produce nutrients for other organisms in the soil. Jansson said measuring how well the microbes chow down on chitin should tell scientists how the carbon-cycling process in space might be affected by factors including zero gravity, space radiation exposure and altered levels of carbon dioxide.
“We wanted to have something that required an interacting community to decompose,” Jansson told GeekWire. “Chitin is a complex polymer, and so it’s difficult for one organism to degrade it all by itself.”
Each set of test tubes will undergo sampling at four different times over the course of 12 weeks. And when the spaceborne samples are brought back from orbit, they’ll be compared with the lab samples that stayed on Earth.
“We have done some preliminary experiments just to see who might be playing well with whom,” Jansson said. “Our hypothesis is that in the space environment, those interactions may be altered because of space conditions. For example, in microgravity, it may be more difficult for these different species to find each other.”
The results of the experiment could guide scientists as they work out the recipes for making soil that’d be suitable for growing crops on spaceships, on the moon or on Mars. Who knows? A blend of bacteria from eastern Washington state just might end up optimizing potato crops on the Red Planet.
