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.
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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.”
Salad
anyone?
Read more at Research.gov.
Bean plant image via Shutterstock.