Preparing for that trip to Mars
These scientists are working to make a human mission to Mars a reality.
From article, (There are many reasons NASA wants to learn to grow vegetables in space. Besides providing fresh food for astronauts, plants can provide life support by recycling air and water. “There’s also the psychological benefit that growing plants may have,” says Gioia Massa. She’s a plant scientist and the head of NASA’s Veggie Project at Kennedy Space Center in Cape Canaveral, Fla.
As Mark Watney learned on Mars, potatoes might be good survival food. They’ve got decent amounts of protein, some vitamins and other nutrients. They’re also rich in carbohydrates (sugars and starches). You couldn’t survive on potatoes alone. They could, however, help to keep you from starvation.
There are some downsides, though. Potatoes need to be cooked before they can be eaten. And potato plants need a lot of room to grow. So Massa and her colleagues started with something easier: lettuce.
In 2014, they sent ISS astronauts a garden. Lettuce seeds were packed into “plant pillows” with baked clay and fertilizer. Add water, some artificial light and voila! The lettuce grew!
But the astronauts couldn’t eat it.
They had to send every bit back to Earth to be studied. The next year, after NASA scientists confirmed this food was safe, the astronauts grew a second crop. This time they were allowed to chow down.
The astronauts used their lettuce to garnish hamburgers. They also made lettuce wraps with lobster salad inside. “They got really creative,” Massa says.
Not surprisingly, gardening is different in space than it is on Earth. Without gravity, plants don’t know which way is up. But they adapt. They send their shoots toward light and their roots in the opposite direction. Fans must circulate air. Otherwise, oxygen would gather in a ball around the plants, and they wouldn’t have enough carbon dioxide to do photosynthesis.
The scientists also had trouble providing the plants enough water. The fabric plant pillows containing the seeds, clay and fertilizer were designed to draw water from a reservoir. But they didn’t work fast enough. The astronauts ended up needing to water the plants by hand. Massa and her team are now redesigning the watering system.
ISS astronauts also have grown Chinese cabbage as well as flowers. In addition to being pretty, astronaut Scott Kelly’s garden of zinnias helped scientists study whether plants flower in space. They do! That’s important to know, because flowering is how some plants reproduce. It’s also part of how some plants make fruit.
Future crops will include a bitter Asian green called mizuna and cherry tomatoes, which astronauts will have to pollinate by hand using a tiny brush. “We don’t have bees up there,” notes Massa. One day, they might also grow peppers and herbs.
While the veggie garden is small for now, eventually it could someday help feed astronauts on long-distance space missions — or a colony on Mars. “Everything we do is a stepping stone,” Massa explains.)
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