This is a pretty fascinating explanation of China’s lunar relay mission, Queqiao, becoming the first relay satellite to serve the far side of the moon.
After a 24-day journey, Queqiao, the relay satellite for China’s Chang’e 4 lunar mission, successfully entered its Earth-Moon L2 halo orbit. A normal mission to lunar orbit usually takes four or five days, but Queqiao took much longer due to its special orbit. Here’s a guide to the spacecraft’s long and complicated journey.
Source: How China’s lunar relay satellite arrived in its final orbit | The Planetary Society