Barely a day has passed since NASA’s momentous flyby of Ultima Thule, and already a new historic space moment is in the works. If all goes according to plan on Wednesday, China will become the first nation to land a spacecraft on the far side of the moon — and attempt to grow living organisms there. The Chang’e-4 spacecraft, now orbiting at nearly 9 miles from the lunar surface, carries a mini-biosphere complete with living silkworm eggs.
Chang’e-4, named for the Chinese goddess of the moon, is carrying a 3-kilogram (6.6-pound) aluminum container housing some potatoes, a few Arabidopsis plant seeds, and, notably, a handful of silkworm eggs. Combined with air, water, and a special nutrient solution, the container constitutes its own complete ecosystem, with the potato and Arabidopsis breathing out oxygen after taking in the carbon dioxide exhaled by the silkworms. The China National Space Administration project’s success will tell us how much the moon’s extremely low gravity affects the growth of living organisms and the quality of the silk spun by the worms.
According to the Chinese news agency Xinhua, the lives of these lunar pioneers will be streamed to Earth via a small camera and data transmission system in the cylinder.
A rendering of Chang'e-4 on the moon.
NASA and other space agencies have grown a variety of plants and raised animals in the International Space Station, but that’s located in low Earth orbit, where gravity is actually about 90 percent of what we experience on land. Meanwhile, the moon’s gravity is only about 17 percent of that on Earth, which makes growing organisms tricky. Chang’e-4’s aluminum biosphere is insulated and equipped with its own energy supply to regulate the moon’s vastly different light and temperature, reports the South China Morning Post, though there’s not much it can do to counteract microgravity. The experiment will reveal how much of a problem this unique environment will be for future lunar farmers.
It’s already clear that lunar farming isn’t going to be easy. As scientists on the ISS have found, water tends to clump together in low gravity; water sprayed onto the base of the plant is likely to “stick to the stem or adhere to the material in which the plant grows,” notes NASA in The Physics of Space Gardens. Scientists writing in the journal PLOS One in 2014 showed that humans require at least 15 percent the gravity of Earth to tell which way is up, so it’s unclear whether plants and worms will grow normally with the moon’s meager 17 percent gravity.
Fortunately, future farmers on the moon’s far side won’t have to worry about constant darkness. Though commonly referred to as the “dark side,” the far side actually gets just as much light as the side facing us — we just never get to see it.
According to a report from TechRadar, Chang’e-4’s landing will be televised on state-run China Global Television Network (CGTN), though an official time has not yet been announced. Inverse will update this story as it develops.
