In an event that is first of its kind, China managed to grow a cotton plant on the far side of the moon. The apparatus for the experiment was placed inside the robotic probe sent to the moon as part of the Chang’e 4 moon mission.
The Chinese team who worked on the project tried to recreate an environment similar to that on the earth. In addition to cotton, they chose four other biological organisms including potato seeds, arabidopsis seeds, yeats, fruit-fly, etc.
At the same time, they managed to keep the weight of the setup under 3 kilograms due to transport limitations and maintain a pressure of 1 atmosphere. However, the plant species still faced microgravity and space radiations on the moon.
What made the situation worse is the massive drop in temperatures as that happens on the moon during the lunar night. Sometimes, it can go all the way down till minus 190-degree celsius. The result was all the organisms except the cotton seeds died because no external heating was provided to the setup.
Although the cotton seeds managed to grow two leaves on the moon, the plant couldn’t live past 1 lunar day which is 14 and a half days on earth.
The experiment started soon after the Chang’e 4 landed on the moon on January 3, 2019. But even after the cotton plant died the team continued it for several months until May to see if the apparatus can survive.
They have also released a 3D reconstructed image showing the two leaves of the cotton plant.
Initially, they also considered sending animals to the moon, for instance, a small tortoise. But the limited oxygen supply in the probe pushed back the plans.
“Even though it is very meaningful to choose tortoise, the oxygen inside the payload can only be used for about 20 days for turtles,” said Xie Gengxin in an interview IEEE Magazine.
Xie and his team at the Technology Research Institute at Chongqing University have designed the experiment. They’ll make efforts to send more complex animals in the future experiments, most probably, Chang’e 6 that is scheduled to happen in the early 2020s.
Anyway, this is not the first veggie experiment that has been done outside of the earth’s atmosphere. In the past, the scientists have achieved success in growing a plant inside in the International Space Center, China just took it one step further – achieving the first biological growth on the moon.