Last August, lettuce became a hero.Astronauts aboard the international space station tasted lettuce grown in space for the first time on August 11, foreign media reported.Scientists see the taste on the tip of the tongue as an important step toward sending a manned spacecraft to Mars.Getting to eat lettuce grown on the space station is something that makes NASA astronauts feel special.The lettuce, which was sent to the space station by the former dragon spacecraft, grew in a special "vegetable box" designed by the orbital technology center in Madison, Wisconsin.
Lettuce seeds are spread on a bed of soil and fertilizer used for germination.Since vegetables cannot be watered in space, special irrigation systems are designed at the bottom of the bedding.Each weighs about 7kg and can be folded or stretched.The box is also equipped with red, green and blue LED lights to promote vegetable growth.
NASA says the international space station has been experimenting with growing vegetables since May 2014. If astronauts could grow their own vegetables after leaving earth, they might be better prepared for the rigors of space exploration that can take months or even years.There is no possibility of regularly resupplying Mars, and astronauts will have to grow their own food to survive the voyage.
With the development of technology, it is very efficient to grow some plants in space.Currently, scientists are studying the planting of a genetically modified dwarf plum tree only about 2 meters in space.But more diverse sources of protein, fat and carbohydrates may be needed, such as tomatoes and peanuts.
But all these efforts will be in vain if the water runs out.On the international space station, the urine-water recovery system needs regular repairs, and astronauts on interplanetary missions can't get new parts back.In this case, gmos may come into play.Michael Flynn, an engineer at NASA's Ames research center, is working on a water filter made of genetically modified bacteria that works like a human intestine recycles what it drinks."Basically, the human body with a life span of 75 to 80 years is itself a water recovery system," Flynn said.The filter, like the human gut, may continue to be self-sustaining.