NASA researchers are developing a greenhouse system that could help sustain astronauts working in deep space.

While NASA has already succeeded with growing plants on the International Space Station, the Prototype Lunar/Mars Greenhouse project aims to make a greenhouse system work on the moon or Mars.

The prototype involves an inflatable greenhouse which recycles nutrients in a loop to simulate processes on Earth that support life.

At the University of Arizona's Controlled Environment Agriculture Center, an 18 foot long (5.5 meters), 7 foot, 3 inch (2.2 meters) diameter lunar greenhouse chamber (pictured) is equipped as a prototype bioregenerative life support system

NASA researchers at the Kennedy Space Center in Florida are collaborating with a university team to develop these long-term methods that could sustain astronauts in space.

'We're working with a team of scientists, engineers and small businesses at the University of Arizona to develop a closed-loop system,' said Dr Ray Wheeler, lead scientist in Kennedy Advanced Life Support Research.

'The approach uses plants to scrub carbon dioxide, while providing food and oxygen.'

The prototype involves an inflatable greenhouse that can be deployed to support plant and crop production for nutrition, air revitalization, water recycling and waster recycling.

This setup is called a bioregenerative life support system.

Dr Wheeler said that when astronauts exhale carbon dioxide which is introduced into the greenhouse, the plants inside can generate oxygen via photosynthesis.

The water cycle inside the greenhouse begins with water that is brought along or found at the lunar or Martian landing area.

Resources such as water that should be available in certain locations on the lunar or Martian surface, which could support missions lasting months or years.

The water is then oxygenated and given nutrient salts, and it continuously flows across the roots of plants, and is returned to a storage system.

Researchers at the University or Arizona in Tucson are testing the Prototype Lunar Greenhouse, including determining what plants, seed or other materials should be taken along to make the greenhouse system work on the moon or Mars.

Learning about what to take and what to gather on site will be crucial for living on locations that are far away.

The researchers say that using resources that using available resources located or frown on site is called in-situ resource utilization, or ISRU.

HOW DOES THE GREENHOUSE WORK? The prototype involves an inflatable greenhouse that can be deployed to support plant and crop production for nutrition, air revitalization, water recycling and waster recycling. This setup is called a bioregenerative life support system. When astronauts exhale carbon dioxide which is introduced into the greenhouse, the plants inside can generate oxygen via photosynthesis. The water cycle inside the greenhouse begins with water that is brought along or found at the lunar or Martian landing area. The water is then oxygenated and given nutrient salts, and it continuously flows across the roots of plants, and is returned to a storage system. The prototypes being developed are cylindrical and and are 18 feet (5.5 meters) long and more than 8 feet (2.4 meters) in diameter. To protect astronauts from space radiation, the greenhouse units would most likely be buried under surface soil or regolith (the layer of loose rocky material covering solid bedrock), thus requiring specialized lighting. 'We're mimicking what the plants would have if they were on Earth and make use of these processes for life support,' said Dr Gene Giacomelli, director of the Controlled Environment Agriculture Center at the University of Arizona. 'The entire system of the lunar greenhouse does represent, in a small way, the biological systems that are here on Earth.' Advertisement

'We're mimicking what the plants would have if they were on Earth and make use of these processes for life support,' said Dr Gene Giacomelli, director of the Controlled Environment Agriculture Center at the University of Arizona and a professor at the Agricultural and Biosystems Engineering Department.

'The entire system of the lunar greenhouse does represent, in a small way, the biological systems that are here on Earth.'

Dr Giacomelli said that the next step will be to use additional lunar greenhouse units for specialized testing to make sure that the system will support a team of astronauts working on the moon or Mars.

'We will develop computer models to simulate what we're doing to automatically control the environment and provide a constant level of oxygen,' he said.

The prototypes being developed are cylindrical and and are 18 feet (5.5 meters)long and more than 8 feet (2.4 meters) in diameter.

To protect astronauts from space radiation, the greenhouse units would most likely be buried under surface soil or regolith (the layer of loose rocky material covering solid bedrock), thus requiring specialized lighting.

Aboard the International Space Station, astronauts have been gaining experience in growing crops in space. Expedition 50 commander Shane Kimbrough of NASA (pictured) harvests lettuce from the Veggie experiment on Dec. 2, 2016. The Veggie Plant Growth System is a deployable plant growth unit capable of producing salad-type crops to provide the crew with a palatable, nutritious and safe source of fresh food

'We've been successful in using electric LED (light emitting diode) lighting to grow plants,' Dr Wheeler said.

'We also have tested hybrids using both natural and artificial lighting.'

Solar light could also be captured with light concentrators that track the sun and then direct the light to the greenhouse chamber using fiber optic bundles.

Although this research is taking place on Earth, NASA's Veggie Plant Growth System was the first American, fresh-food growth experiment on the International Space Station.

It helped continue research for the development of food production systems for long-duration space explorations missions.

'I think it's interesting to consider that we're taking our terrestrial companions with us,' said Dr Wheeler.

'While there may be ways to engineer around it in terms of stowage and resupply, it wouldn't be as sustainable.

'The greenhouses provide a more autonomous approach to long-term exploration on the moon, Mars and beyond'