Gardens in space
Catching floating raindrops, soil and seeds are making gardening just that much harder in the International Space Station. But this is how the astronauts function in their weightless environment. Even the plants don't know which way to grow. Without gravity the soil and water simply float away unless contained; plant roots grow every which way. Without gravity the plant doesn't know what is up or down. There is no rising or setting sun, just a 24 hour a day grow light.
But as Spacex-3 blasted off from Cape Canaveral on April 18th, there was a growing new hope. Gioia Massa of the Kennedy Space Center leading the new team says, "We call it 'Veggie', a plant growth chamber designed to make gardens thrive in weightlessness."
Veggie's heritage traces back decades to plant experiments on board the Russian space station Mir and NASA's space shuttle. To date, NASA astronauts have never tasted home-grown space food. But that could soon change with something called 'plant pillows'.
"Basically, these are bags of 'space dirt' and slow-release fertilizer," explains Trent Smith, the project manager from KSC. "Wicks inserted into the bags draw water into the soil where it cannot float away."
In addition to guiding water, the wicks act as a kind of gardening stake.
"The wicks are where we glue the seeds," continues Massa. "We have to be very careful to orient the seeds so that roots grow 'down' into the soil and shoots pop out of the bag."
When the shoots emerge, they find an array of overhead LEDs, providing light for photosynthesis and a sense of direction. The bellows-like chamber walls allow expansion for the growing crop.
Pictures of Veggie often show the chamber flooded with a mixture of red and blue light the color plants use most for photosynthesis. Under a purplish light, plants appear gray and unappetizing. But by adding green light the new light becomes white giving the garden a better effect.
The garden's appearance is important for both psychologically and nutritionally. Spaceships provide a relatively lifeless environment: cold, metallic and sterile. "Plants allow astronauts to form a connection to living things," she says. "There could be a huge psychological benefit."
Massa says the first crop of Outredgeous should be ready for harvesting in late May, but astronauts won't be allowed to taste-test.
"First, we have to bring the lettuce home for analysis," she explains. Is it safe to eat? Are there bacteria growing on the leaves? "These are some of the questions we'll be looking at. If everything checks out, future crops may be eaten."
Read more at Research.gov.
Bean plant image via Shutterstock.