[phys.org] Future astronauts could enjoy fresh vegetables

[Orionid]

Future astronauts could enjoy fresh vegetables from an autonomous orbital greenhouse
FEBRUARY 27, 2020 by Universe Today


Credit: TPU

If humanity is going to become a spare-faring and interplanetary species, one of the most important things will be the ability of astronauts to see to their needs independently. Relying on regular shipments of supplies from Earth is not only inelegant; it's also impractical and expensive. For this reason, scientists are working to create technologies that would allow astronauts to provide for their own food, water and breathable air.

To this end, a team of researchers from Tomsk Polytechnic University in central Russia—along with scientists from other universities and research institutes in the region—recently developed a prototype for an orbital greenhouse. Known as the Orbital Biological Automatic Module, this device allows astronauts to grow and cultivate plants in space, and could be heading to the International Space Station (ISS) in the coming years.

Since the beginning of the Space Age, numerous experiments have demonstrated that plants can be cultivated under microgravity conditions. However, these studies were carried out using greenhouses located in the living compartments of orbital stations, and involved significant limitations in terms of technology and space.

For this reason, a research team from TPU began working to scale and improve the technologies necessary for cultivating important agricultural crops. The project team includes additional researchers from Tomsk State University (TSU), Tomsk State University of Control Systems and Radioelectronics (TUSUR), the Institute of Petroleum Chemistry and the Siberian Research Institute of Agriculture and Peat.


Plants cultivated in the TPU autonomous greenhouse. Credit: TPU

As Aleksei Yakovlev, head of the TPU School of Advanced Manufacturing Technologies, explained in a TPU News release: "Currently, we are preparing an application for the experiment and working through the preliminary design and technical solutions. In 2020, we should complete the application and submit it. Then, a coordination council will evaluate its relevance and importance. It tends to take a year and a half from the application to the start of the experiment, so we expect to join a long-term program and receive funding in 2021."

The smart greenhouse project will incorporate technologies developed at TPU, which include smart lighting to accelerate plant growth, specialized hydroponics, automated irrigation, and harvesting solutions. At present, TPU is constructing a new testing ground so they can expand production on the smart greenhouse.

"In Tomsk, we will conduct interdisciplinary studies and solve applied problems in the field of agrobiophotonics," said Yakovlev.


The prototype greenhouse is being designed to provide astronauts with a continuous vegetarian diet. Credit: University of Arizona

In the end, Yakovlev and his colleagues envision an autonomous module that would be capable of supplying food for astronauts and potentially even docking with the ISS. They also indicated that the module would contain a cultivation area measuring 30 m² (~320 ft²) and that it would be cylindrical in shape. Yakolev indicated that this would allow the module to be spun up to simulate different gravity conditions:

"The gravity index will be set by the rotation speed of the module around its axis. We also expect that the module will be made of flexible material to compact assembly and automatic orbital unpacking."

These include the gravity conditions that are present on the moon and Mars, which experience the equivalent of about 16.5% and 38% Earth gravity (0.1654 g and 0.3794 g), respectively. At present, it is unknown how well plants can grow on either body and research to that effect is still in its infancy. Hence, the information provided by this module could prove useful if and when plans for a lunar and/or Martian colony are realized.


Dwarf wheat growing in the Advanced Plant Habitat. Credit: NASA

The design and engineering that goes into the module will also take into account the kinds of conditions that are present in space, such as solar and cosmic radiation and extremes in temperature. Beyond that, the module will investigate what kinds of crops grow well in orbit. Yakovlev said, "Another important issue is the selection of necessary and most suitable agricultural crops and their protection against pathogens in microgravity. We offer various types of lettuce, leeks, basil and other crops for cultivation in the module."

Three TPU experiments were recently approved for transport to the ISS and will be implemented later this year. They include a device capable of 3-D printing composite materials, housings for a swarm of satellites, and a multilayer nanocomposite coating that will be applied to the ISS portholes to protect against micrometeoroid impacts (Peresvet). Their implementation will begin later this year and in 2021.

Source: https://phys.org/news/2020-02-future-astronauts-fresh-vegetables-autonomous.html

[Orionid]

Space lettuce: Nutritious and safe crops would be a dietary supplement to assist long-distance space missions
by Frontiers MARCH 6, 2020 [phys.org]


Astronaut Steve Swanson harvests some of the crop in June 2014. Credit: NASA

Astronauts in space live on processed, pre-packaged space rations such as fruits, nuts, chocolate, shrimp cocktails, peanut butter, chicken, and beef to name a few. These have often been sterilized by heating, freeze drying, or irradiation to make them last and key a challenge for the US Space Agency NASA has been to figure out how to grow safe, fresh food onboard.

In a new study in Frontiers in Plant Science, Dr. Christina Khodadad, a researcher at the Kennedy Space Center, and co-authors report the successful cultivation of a salad crop—red romaine lettuce of the 'Outredgeous' cultivar—on board the International Space Station (ISS). They show that space-grown lettuce is free of disease-causing microbes and safe to eat, and is at least as nutritious as Earth-grown plants. This is despite being grown under lower gravity and more intense radiation than on Earth.

Apart from a welcome change in diet, fresh produce would provide astronauts with additional potassium as well as vitamins K, B1, and C—nutrients that are less abundant in pre-packaged rations and tend to degrade during long-term storage. Additionally, growing crops would be especially useful on long-distance space missions, like the upcoming Artemis-III missions (scheduled to land humans on the lunar South pole by 2024), the current SpaceX programme, and NASA's first crewed mission to Mars, planned for the late 2020s.

"The ability to grow food in a sustainable system that is safe for crew consumption will become critical as NASA moves toward longer missions. Salad-type, leafy greens can be grown and consumed fresh with few resources," says Khodadad.


Astronauts Scott Kelly and Kjell Lindgren taste the lettuce grown onboard the ISS in August 2014. Credit: NASA

Between 2014-2016, lettuce was grown on board the ISS from surface-sterilized seeds within Vegetable Production Systems (nicknamed "Veggie"), growth chambers equipped with LED lighting and a watering system, specifically designed to grow crops in space. The crops grew undisturbed inside the Veggie units for 33 to 56 days, until crew members ate part of the mature leaves (with no ill effects!). The remainder was deep-frozen until transport back to Earth for chemical and biological analysis.

As a control, the scientists grew control plants on Earth under the same conditions, which was possible because temperature, carbon dioxide, and humidity data were logged on board the ISS, and replicated in the Kennedy Space Center's laboratories with a 24-48 hour delay.

Space-grown lettuce was similar in composition to the Earth-grown controls, except that in some (but not all) trials, space-grown plant tissue tended to be richer in elements such as potassium, sodium, phosphorus, sulphur, and zinc, as well as in phenolics, molecules with proven antiviral, anticancer, and anti-inflammatory activity. Space- and Earth-grown lettuce also had similar levels of anthocyanin and other antioxidants, which can protect cells from damage by free, reactive oxygen radicals.

The researchers also examined the microbial communities growing on the plants. Typical Earth-grown plants harbour a diverse set of microbes. These may include specialized, beneficial guests called commensals (which neither harm nor benefit their host), or haphazard associates. Because these can affect the health of plants and their suitability as food, the researchers used next-generation DNA sequencing technology to characterize the communities of fungi and bacteria growing on the lettuce.


Astronaut Shane Kimbrough in front of the 'Veggie' chamber on the ISS in November 2016. Credit: NASA

They identified the 15 most abundant microbial genera on the leaves and 20 in the roots, and found that the diversity and identity of these microbes was similar for space- and Earth-grown lettuce. This similarity was surprising, given the unique conditions in the ISS: the scientists had instead expected that these would favour the development of distinct microbial communities.

Importantly, none of the detected bacteria genera are known to cause disease in humans. Further tests confirmed that the leaves never carried any dangerous bacteria known to occasionally contaminate crops, such as coliform E. coli, Salmonella, and S. aureus, while the numbers of fungal and mould spores on them was also in the normal range for produce fit for human consumption.

The authors conclude that lettuce grown in space-borne Veggie units is safe to eat. These encouraging results open the door for experiments with other nutritious and tasty crops onboard the space station, to help propel astronauts further into space.

"The International Space Station is serving as a test bed for future long-duration missions, and these types of crop growth tests are helping to expand the suite of candidates that can be effectively grown in microgravity. Future tests will study other types of leafy crops as well as small fruits like pepper and tomatoes, to help provide supplemental fresh produce for the astronaut diet," concludes co-author Dr. Gioia Massa, project scientist at Kennedy Space Center.

Sources: https://phys.org/news/2020-03-space-lettuce-nutritious-safe-crops.html

https://www.frontiersin.org/articles/10.3389/fpls.2020.00199/full?fbclid=IwAR1HccMzhJ2dK5pD9A_2z77dyJVgVl9pSPei5pEBrpp9m7TKI7rTbO5213k