One year ago, China’s Chang’e 4 probe and the Yutu-2 rover it carried onboard have been busy photographing and scanning minerals, growing yeast, hatching fruit-fly eggs, and cultivating cotton, potato, and rapeseeds on the dark side of the moon. Last summer, NBC News reported that the Yutu-2 rover had come across a strange “gel-like” substance which the Chinese began to study.