Chinese Astronauts are Growing Rice on the Tiangong Space Station

The Chinese space station is now a mini garden of rice and edible weed.

Astronauts at China's Tiangong-2 space station are growing rice and thale cress (Arabidopsis thaliana) - a kind of edible weed - in microgravity. According to Chinese new sources, the rice plants have grown 10 centimeters tall and the cress plants have already flowered.

The purpose of the experiment is to find out whether plants in space still grow according to an Earth-based cycle and yield the same seeds.

"We want to study the growth rhythm and the flowering of plants in micro-gravity conditions," Zheng Huiqiong, chief scientist for plant research on Tiangong-2 and a researcher at the Institute of Plant Physiology and Ecology of the Shanghai Institutes for Biological Sciences under the Chinese Academy of Sciences (CAS), told Chinese media outfit Xinhua.

"So far the plants on Tiangong-2 have been growing well. Some Arabidopsis thaliana are blooming, and the rice is about 10 centimeters tall," Zheng added.

Chinese taikonauts Jung Haipeng and Chen Dong launched aboard the Shenzhou 11 spacecraft and successfully docked to the experimental space lab on Oct. 18. Both will complete a 30-day mission - the longest Chinese mission in space. When the two astronauts return to Earth in November, they will be bringing back samples of the thale cress grown in the lab, which is expected to yield seeds in space.

The rice experiment will continue on Tiangong-2 for about half a year - the longest Chinese space-based plant-growing experiment. According to Zhang Tao, a researcher at the CAS Shanghai Institute of Technical Physics, a special incubator was designed for Tiangong-2 so scientists on Earth could "remotely control the lighting, temperature, humidity and volume of the nutrient solution during the experiment."

An experiment involving six silkworms is also aboard the space station. According to a report by New Scientist, the silkworm experiment - designed by middle school students in Hong Kong - could be protein sources for long space journeys.

While the Tiangong-2 experiment is the first to use a remotely controlled incubator environment, it was not the first time food was grown in microgravity. Astronauts aboard the International Space Station (ISS) had grown and eaten the first on-orbit lettuce.