That's one giant leap for China.
China state television announced Thursday that China's Chang'e 4 lunar explorer, which launched in early December, "became the first ever probe to soft-land on the far side of the moon." The probe touched down at 10:26 Beijing time, the China Global Television Network said.
The landing "lifted the mysterious veil" from the far side and "opened a new chapter in human lunar exploration," the broadcaster said, according to Reuters. (A soft landing is where a lander touches down as gently as possible; it is preferable to a hard landing.)
The six-wheeled rover landed in the southern section of the Von Kármán crater, near the moon's south pole, Chinese media reported. China's Xinhua News published a photo it says was taken by the probe "on the never-visible side of the moon." While photos of the normally hidden far side of the moon have been previously taken from space, this would be the first image ever captured from the surface.
China's lunar lander is loaded with a variety of cameras and sensors, including ground-penetrating radar to peer beneath the lunar surface, reported NPR's Joe Palca while the probe was en route. "Although Chang'e 4's mission is largely scientific, it is also a key bit of preparation for sending Chinese astronauts to the lunar surface," wrote Palca. Only 12 humans have ever set foot on the moon, and all of them were Americans.
The far side of the moon is "actually much more primitive" than the near side, with "really ancient crust that dates back to the very, very early solar system," said Briony Horgan, a planetary scientist at Purdue University, previously told NPR.
"There are rocks all over the far side that are over 4 billion years old," she said. "We're really excited to see what those look like up close."
The far side is sometimes erroneously referred to as the "dark side" of the moon, even though it does get sunlight. Traveling to the far side of the moon presents certain technical challenges — namely, it makes communication harder. Whereas Earth-bound scientists can communicate with the near side using direct radio communication, China first had to send a communications relay satellite to orbit above the far side of the moon, according to NASA. That satellite, the Queqiao, launched in May and entered orbit around the moon three weeks later.
"Queqiao means 'Bridge of Magpies,' referring to a Chinese folktale about magpies forming a bridge with their wings to allow Zhi Nu, the seventh daughter of the Goddess of Heaven, to reach her husband," NASA wrote.