Space is just an another surviving place instead of earth where in future humans are going to live there in vast numbers and in other words; it will become a whole new habitat or the next suburb which finally establishes the huge space world. For establishing the space world, orbiting laboratories such as International Space Station (ISS) worked on various colonization projects, but when we intend about the colonies in the space there are lots of questions arises in our mind such as : How do we feed people living in space? How do we provide the air they will breathe? How do we fulfill our daily need? etc; these necessities must be accomplished by space farms, Space farming simply refers to growing plants in space or creating earth like condition or something close to it for build up the new farms.
NASA (National Aeronautics and Space Administration) has carved a niche in this direction and opened up new avenues for various space researchers and currently they have started an on-orbit plant growth that could eventually facilitate longer missions on the space station or even permanent habitation on space. But constitution is not an easy task, NASA and the Air Force have done research on space farming and closed ecologies for over twenty years, there are heaps of challenges comes in front of establishing the space farms i.e. less gravity or zero gravity, varying rooting material, artificial lighting, contaminants and limited space available for farming etc. (Jessika Toothman) Current space-farming experiments examine different aspects of farming in microgravity (a state of very low gravity); different types of cultivation systems are used for this purpose like Advanced Astroculture (ADVASC), European Modular Cultivation System (EMCS).
The ADVASC is the first system being used to grow plants on the Space Station, with the help of orbital laboratory (International Space Station), group of engineers and scientists at the Wisconsin Center for Space Automation and Robotics (WCSAR), University of Wisconsin-Madison, formulate a plant growth unit capable of supporting plant growth in the microgravity environment.
• ADVASC was designed to operate relatively autonomously (continuously for an average 180 days in a microgravity environment) providing temperature, humidity, lighting control, nutrient delivery, and data downlink with minimal crew assistance.
• ADVASC explored the benefits of using microgravity to create customized crops that withstand disease and inhospitable conditions, resist pestilence, and need less space to grow.
• The video and computer support controlled through the ADVASC-Support System sent data directly to investigators at Wisconsin Center for Space Automation and Robotics (WCSAR) via the Telescience Resource Kit (TReK) system.
• The crew provided on-orbit support, using syringes to take samples and making sure the hardware was operated normally.
For conducting this experiment they chose the Arabidopsis thaliana (Brassicaceae family) as a model plant (i.e. very easily grown in the extremely restrictive conditions aboard the Space Station, a completely sequenced genome, experimental results are easily analyzed and a history of space experiments) and the aim of the first Advanced Astroculture experiment are to determine whether ;
• this plant can complete its seed-to-seed life cycle in microgravity;
• to determine the impact of microgravity on the gene expression levels - the plant's traits that are determined genetically;
• and to facilitate comparison between the chemical characteristics of the seeds produced in space with seeds harvested on Earth.
Arabidopsis plants (thale cress) grew and completed a full life cycle in microgravity as well as the postflight morphometric analyses manifest that Arabidopsis thaliana does not require the presence of gravity for growth and development and this experiment demonstrated that ADVASC is capable of providing environment conditions suitable for plant growth and development in microgravity. During a two-month growth period, the plants progressed from seed hydration to germination, vegetative, and reproductive stages, producing mature seeds. Ninety percent of the seeds germinated in space, although only seventy percent of the plants grew to maturity. Some of the seeds that were harvested from the plants grown in microgravity were planted in a ground study. These seeds produced typical plants without any visible abnormalities.
During a second ADVASC run, second-generation seeds were produced and tissues were harvested and preserved for RNA and complementary deoxyribonucleic acid (cDNA) analysis. Detailed results of the germination and harvesting of space-grown seeds in the ADVASC growth chamber in the U.S. Destiny Laboratory have not been released.
In the third ADVASC run, which took place over approximately 95 days on ISS soybeans (Pioneer Brand 9306) were also grown from seed to seed for the first time in space. Biomass production in the space seeds was approximately 4 percent larger than ground controls. Flight and grounds controls produced nearly identical numbers of seeds, but the space seeds were larger on average. Scientists found that the seeds produced in space were healthy, the germination rates were comparable to those on Earth, and no major morphological differences were evident. Phytochemical analysis of commercially important components such as oils, amino acids, proteins, carbohydrates, and phytoestrogens have not yet been released but changes have been reported in the pattern of gene expression in Arabidopsis on exposure to microgravity.
Another system called European Modular Cultivation System (EMCS) system permits for the cultivation, stimulation and crew-assisted operation of biological experiments under well-defined conditions (e.g., illumination, temperature, atmospheric composition, and water supply).
• It includes two centrifuges that can provide artificial gravity at levels ranging from 0 to 2 g.
• The EMCS facilitates long-term growth studies, including multi-generation (seed to seed),
• studies on early development, to determine the influence of gravity on early development and growth (g-level threshold research),
• And studies of how plants perceive and respond to gravity when they grow.
• EMCS operates autonomously; the facility can be controlled by the ground via a TeleScience Support Center or by the crew via the Expedite the Processing of experiments to Space Station (EXPRESS) laptop computer.
The EMCS can also be adapted to different applications which will moved it towards the advancement like microscopic observation of plants, on-signal perception, transduction in plant tropisms, possibilities for the research on microbes, insects or amphibians, aquatic species, plant, tissues and cell cultures, also on radiation effect, this provides the next step in the development of advanced facility dedicated to the biological research in space.
Instead to these two cultivation systems, the Lada Greenhouse was also developed as a cooperative effort between Space Dynamics Laboratory at Utah State University and Russia's Institute of Biomedical Problems. Named for the ancient Russian goddess of spring, the wall-mounted Lada has been in use in the Zvezda module of the space station since 2002, when it was delivered aboard a Russian Progress spacecraft. It consists of Control unit; Lighting unit; Leaf chamber; Root module; Water canister. Being a module-type system, the Lada greenhouse ensures maximum flexibility and with the help of this we will able to ensure that the space-grown crops are safe to eat.
Microgravity can also be affects on the function of rooting material; researchers are experimenting with many possibilities, including clay particles, hydroponics and a material like peat-moss and they are also studying whether any contaminants and dangerous organisms from space will affect those space-grown plants, making them inconsumable for humans and from these lists of challenges, one of the biggest challenge is limited space available in the confined quarters of spacecraft as compared to rolling farmlands on Earth. Researchers must develop an efficient, streamlined apparatus that can hold crops as they grow with limited space. Growing machines must be automatic and be able to regulate watering, humidity, lighting, air circulation and nutrient delivery. These growing machines also need to integrate with the life support system to successfully exchange carbon dioxide and oxygen. With these considerations in mind the scientists usually focuses on plants that give high yield of edible parts and can flourish in small spaces. Researchers have begun to grow a variety of plants in space, including thale cress, lentils, wheat, leafy salad plants, field mustard plants and soybeans.
Scientists at Purdue University suspect the low-maintenance Seascape cultivar -- a cultivated variety of strawberry -- is up to the challenge. These berries are big, red and just as tasty as the ones at our local farmer's market. Various plant specimens that were growing at the International Space Station were brought back by the Discovery space shuttle in April and are now being examined by researchers. It will take about a year before we hear the results, but astronauts everywhere are probably crossing their fingers.
At the end, the overall impact of the space farming will gives assistance to the researchers for understanding and overcome the obstacles which come in the way of establishing the space world and our sparkling future.
About Author / Additional Info:
An Author from India, Research scholar at Central University of Gujarat (CUG) (science technology innovation policy), Worked as RESEARCH ASSOCIATE at CSIR-NISTADS (2011-2012), M.Sc biotechnology from ITS Paramedical college, Gzb. (C.C.S University, Meerut).