NASA develops inflatable greenhouse to grow crops on the moon and Mars

Discoveries & Research

NASA scientists designed an inflatable cylinder greenhouse that could help astronauts grow food when arriving at other planets. Astronauts have successfully grown vegetables and plants aboard the International Space Station, but with the newest project, NASA expects to develop long-term methods to help sustain astronauts working in deep space.

The project is being developed by NASA scientists at the Kennedy Space Center in Florida and researchers from the University of Arizona.

The Prototype Lunar/Mars Greenhouse aims to sustain vegetarian diets for astronauts on locations such as the moon or Mars.

Inflatable prototype greenhouse will allow astronauts grow crops and plants in outer space

The Prototype Lunar/Mars Greenhouse project will support current research in space to cultivate and grow vegetables for food, as well as growing plants to sustain life support systems.

“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 scientists at Kennedy Advanced Life Support Research, according to NASA. “The approach uses plants to scrub carbon dioxide, while providing food and oxygen.”

The prototype consists of an inflatable, deployable greenhouse designed to support plant and crop production. Such production will support astronauts’ nutrition and will help with the air revitalization, waste recycling, and water recycling. The process is known as a bioregenerative life support system.

Wheeler explained that astronauts exhale carbon dioxide, which is introduced into the inflatable greenhouse, thus allowing the plants to generate oxygen through photosynthesis. The water cycle will start with water that is brought along to the landing site or found at the lunar or Martian terrain. The water is then oxygenated, packed with nutrient salts, and then it will continuously flow across the roots of the plants and returned to the storage system.

Tests conducted by the University of Arizona in Tucson have been assessing which plants or seeds should be taken along to make the Prototype Lunar Greenhouse work on either the moon or Mars. These tests are crucial, as it is important to learn which resources will be needed to take along on the mission and which resources can be found on location. Such practice is called in-situ resource utilization, and NASA conducts to better prepare for long distance missions.

NASA engineers and scientists are currently developing systems to harness resources like water, which should be available in some regions of the Martian or lunar surface, to support long-lasting missions.

“We’re mimicking what the plants would have if they were on Earth and make use of these processes for life support,” explained 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.”

Giacomelli, who’s also a professor in the University of Arizona’s Agricultural and Biosystems Engineering Department, noted that the next step of the project is to use additional lunar greenhouse units designed for testing to make sure the system being developed will be able to support a crew of astronauts working on lunar or Martian surfaces.  Giacomelli added that they will also develop computer models to simulate the work they’re doing, to automatically control the environment and provide a stable level of oxygen.

Prototype Lunar Greenhouse will be placed underground

According to a statement from the University of Arizona, the Prototype Lunar Greenhouse (LGH) is hoped to help fulfill the late Ralph Steckler’s dream of space colonization. They note that the LGH aims to deliver more than sustained human presence in space, as the LGH also aspires to bring efficient commercial-ready technology to Earth.

Dr. Roberto Furfaro is the lead investigator from the University of Arizona for the current phase of the project. Furfaro is a professor in the Systems and Industrial Engineering Department within the College of Engineering. The prototypes of the lunar greenhouse currently being developed are cylindrical, measuring 18 feet long and more than 8 feet in diameter. The prototypes were built by Sadler Machine Company, one of the project partners.

To guard the greenhouse against space radiation, the units would likely be buried under surface soil or regolith, which is why they’d require specialized lighting.

“We’ve been successful in using electric LED (light emitting diode) lighting to grow plants,” noted Wheeler. “We also have tested hybrids using both natural and artificial lighting.”

Scientists believe solar light could be captured with light concentrators that are designed to track the sun and then convey the light to the chamber employing fiber optic bundles. Although studies in working on the surface of other planets are being carried on Earth, astronauts aboard the space station have been gaining experience growing crops in space. The first project of this kind was NASA’s Veggie Plant Growth System.

Wheeler notes that it’s interesting to consider that astronauts would be taking our terrestrial companions with them into space, using the greenhouse. He explains that although there are already ways to “engineer” around the problem in terms of stowage and resupply, it wouldn’t be as sustainable and the greenhouse provides an autonomous approach to long-term exploration in the moon or Mars.