American astronaut Scott Tingle has tweeted a picture of red romaine lettuce that is being grown on the International Space Station (ISS) as part of NASA’s experiment to explore the possibilities of growing food in space.

Scott Tingle and other NASA astronauts are currently growing three different varieties of vegetables on the ISS, according to BT. These are (1) red romaine lettuce, (2) Tokyo bekana cabbage, and (3) Japanese mizuna mustard.

The vegetables are being grown in the “Veggie” plant growing facility on the ISS. This fully enclosed, plant-growing chamber was installed in November last year, according to Space.com. This chamber allows plants to grow under blue, red, green, and white LED lights. It also features approximately 180 sensors to provide NASA scientists detailed information about the level of oxygen, moisture, temperature, etc., within the “Veggie” chamber.

According to NASA, this experiment will enable it to investigate the effect of microgravity on the plant growth. As these vegetables grow on the ISS, the crew will get the opportunity to eat them. The outer leaves of the space-grown greens will be picked by the astronauts as needed, but the central part of the plant will be left to develop further. Some samples will also be sent back to the Earth to allow scientists to carry out further experiments on these vegetables.

Having some great success growing lettuce on @Space_Station! pic.twitter.com/ERjN3MmWwO — Scott D. Tingle (@Astro_Maker) March 2, 2018

NASA is currently working to send manned missions to Mars in next 10–15 years, and therefore it understands the significance of space-grown food for astronauts during deep space missions. According to NASA, earlier plant-growing experiments on the ISS focused on enhancing the productivity of crops in controlled environments. The limited space on ISS, however, makes it difficult to carry out large-scale production experiments in space. The current “Veg-03” tests will allow scientists to determine which types of microorganisms could develop in space-grown lettuce and cabbage, thereby providing the initial data for future crop-growing efforts. The results of these experiments will also enable scientists to improve agricultural and biomass production on Earth.

Another aim of these experiments is to assess the impact of space gardening on the mood and morale of the astronauts in space.

Space missions are usually stressful for most astronauts who have to spend long periods of time in microgravity conditions while being away from their family and friends. However, some studies have suggested that space gardens could be psychologically beneficial to the astronauts.

Last year, a study carried out by a team of researchers at the University of Florida, Gainesville, suggested that gardening could provide astronauts the same peace of mind in space as it does back on earth, as reported by Space.com. According to these researchers, humans have an inherent affinity for other life-forms, and therefore plants could help boost the mood and morale of the astronauts in space.