A WAY TO GROW CROPS BEYONG THE EARTH……..
Ensure the “Food security” is a challenge which should be faced by the world in the presence because of the population increment of the world and thereby the increment of food requirement. . For that, an adequate food production is required. To overcome this the world is trying to increase the total crop production by increasing the crop productivity and expanding cultivated area. But expanding the cultivated area is again a challenge because now the majority of arable lands on earth have been already utilized for crop production or for urban infrastructure. And also if people are willing to have base or colony on mars or some other planets it is better if they grow crops there. Therefore, can we grow crops beyond the earth? Of cause, “space farming” is the answer. In this article, some information about the space farming technics, its background information and some of the related experiments have been included.
First, let’s have a look on what is “space farming”. Space farming is cultivation of crops for food or as other materials, in space or on off-earth objects. Actually, this is more or less similar to agriculture on earth but some limitations in space have been done some differences in the cultivation processes. Limitations can be occurred because of the differences in input availability for crop growth like soil media, availability of CO2, availability of water, nutrients, microgravity and so forth in the space. Space farming is being done in International Space Station (ISS) and in tests have been done for future moon or mars based agriculture.
NASA and other agencies have done experiments with plants in space for decades. The six astronauts who are living in International Space Station (ISS) were the first people who have eaten food grown in the space. When consider the space farming in ISS, it is done due to aesthetic and practical reasons. Giving a pleasant environment for astronauts to help them with keeping their psychological well-being, avoiding vitamin deficiencies and providing astronauts with an easily absorbable, long-lasting nutrient source rather than providing prepackaged meal are the objectives of NASA of this space farming. But, the challenge is that how this could be done in an environment without sun light and gravity. However, several interesting technologies and experiments for this have been done and some of them are discussed in this article.
When consider about the technics developed for space farming, I would like give you some important facts about two of the technics which are interesting. They are LED systems and technology of getting texts from plants.
- LED systems- LEDs are very efficient since they waste almost no energy on heat but their output can be vary, which allow them to provide light for specific plant species at specific growth stages. Therefore, a LED lightning system was developed for ISS.
- Technology of getting texts from plants- Since the astronauts; the caretakers of the plants don’t have a lot of time to check the status of plants, they have come up with a solution. They have a sensor which is based on electrical impulses to measure leaf thickness which is as an indicator of crop water content. So, the thirsty plants can send a text for asking water.
Growing plants in microgravity is a challenge and gravity affects root development, nutrient uptake and microbiological interactions. When the gravity is absent plants use other environmental factors as light to guide its growth. “Veggie” is a vegetable production system which was already experimented in ISS in order to help NASA to study plant growth in microgravity.
The veggie garden is like a carry on piece of luggage with only six plants. Each plant has its own growth media called “pillow” which is made out of clay based growth media and fertilizers. The pillow component is very important since it helps to distribute water, air and nutrients around root system in a balanced way. For the light supply, LEDs are used and since plants reflects lot of green light while using red and blue wavelengths more, the veggie chamber glows in magenta pink.
Veggies has grown three types of lettuce, Chinese cabbage, mizuna mustard, red Russian kale and zinnia flowers. Fortunately, no harmful contaminators have affect to the produce so far. The crew members are looking forward to planting more crops as tomatoes and pepper.
Advanced Plant Habitat
This is another technology which is used for space farming. Advanced Plant Habitat (APH) is a chamber for plant based researches on space. As mentioned above, in this method also LED lightening and porous clay media are used with controlled release fertilizer. But in here whole process is automated and does not need the day to day care. And also it uses colored LED s as red, green, blue, white, far red and infrared. The products are not used for their consumption and they are sent to earth for researches. Their attention goes to what happens to the genes, changes in protein metabolic levels and relationship between microgravity and plant lignin content when they are grown in the space. Space causes bones and muscle loss in human. Lignin have functions which are close to bones of human. So, what will be happened for lignin of plants in space? Therefore, experiments are conducting with genetically changed plants with less lignin and they believe that those plants have better nutrient absorption and make easy to compost the plant waste in space.
Biological Research in Canisters
The specialty in this facility is that, this is used for study the effect of space for small organisms like mosses, algae and cyanobacteria who can be grown in petri dishes. In here also LED lightening is used and researches interested about the gene expression changes in the space. Some plants showed new patterns with immune system of them. And also, there are evidences saying that plants in space are struggling to protect from pathogens.
Since “space farming” is an interesting and broad field there are lot of details related to it. Here we have considered only about the space farming in space stations. But, there are experiments on growing crops in mars and moon. They have even harvested peas and tomatoes using mars and moon soil simulant. All the space farming experiments will be very useful in the future for colonization in space and for fulfill the food requirement of people.
- Growing plants in space at www.nasa.gov
- NASA is everywhere: Farming Tech with Roots in Space at www.nasa.gov
- First tomatoes and peas harvested on mars and moon soil simulant by wageningen university
- Space farming yields a crop of benefits for earth at www.nasa.gov