China's Chang'e-6 probe has left a memorable mark on the far side of the moon. The Chinese national flag, unfurled on the probe's lander on Tuesday, will remain intact for a long, long time because it's made from a type of stone, or more precisely, fiber from basalt.

Professor Zhou Changyi, with the National Space Science Center of Chinese Academy of Sciences, also chief designer of the Effective Payload System of Chang'e-6 probe, told CGTN that the flag could stay on the moon for over 10,000 years.