Detector successfully landed on the back of the moon and returned to the world's first close-up shot.

Von Kármán is a lunar impact crater that is located in the southern hemisphere on the far side of the Moon. The crater is about 180 km in diameter and it is located within an even larger impact crater known as the South Pole–Aitken basin of roughly 2,500 km (1,600 mi) in diameter and 13 km (8.1 mi) deep. https://en.wikipedia.org/wiki/Von_K%C3%A1rm%C3%A1n_(lunar_crater)

[Translated from Chinese ~ Release date: January 03, 2019]

"At 10:26 on January 3, the No. 4 detector successfully landed on the back of the moon at a distance of 177.6 degrees east longitude and 45.5 degrees south latitude, and passed back to the world's first close range through the "Bridge Bridge" relay star. The photograph of the moon back image reveals the mystery of the ancient moon back. The mission realized the first soft landing of the human detector and the relay communication of the first moon back with the earth, which opened a new chapter in human lunar exploration.
　　
　　At 10:15, the scientific and technical personnel issued instructions at the Beijing Aerospace Flight Control Center. The No. 4 detector began to reduce the power from the distance of 15 km from the moon. The 7500N variable thrust engine was turned on, and the speed of the detector was gradually increased from the relative 1.7 km to the moon. Drop to zero every second. At 6-8 km, the detector performs rapid attitude adjustment and keeps approaching the moon; it starts hovering at a distance of 100 meters from the lunar surface, identifies obstacles and slopes, and autonomously avoids obstacles; after selecting a relatively flat area, Start slowly and vertically down. About 690 seconds later, the No. 4 detector landed autonomously in the von Carmen crater in the Antarctic-Aitken Basin on the back of the moon. During the lunar landing, the landing camera captured multiple landing area imagery.
　　
　　After the moonfall, under the ground control, through the relay communication link of the "Bridge Bridge" relay star, the 嫦娥4 detector carried out a number of tasks such as the sunwing and directional antenna deployment, and established a directional antenna high-speed link. . At 11:40, the lander surveillance C camera acquired the world's first close-up image of the moon's back and passed it back to the ground. The picture shows the direction of the patrol that is about to leave the lander and sail towards the moon.
　　
　　The 嫦娥4 detector consists of a lander and a patrol. A total of 8 payloads including 2 international cooperative loads are installed. The landformer is equipped with a topographic camera, a landing camera, a low-frequency radio spectrum analyzer, and cooperates with Germany. Four loads such as lunar neutrons and radiation dose detectors; panoramic cameras, moon-receiving radars, infrared imaging spectrometers, and neutral atomic detectors in cooperation with Sweden are installed on the patrol. These instruments will conduct low-frequency radio astronomical observation and research on the back of the moon through in-position and inspection. The patrol area morphology, mineral composition and lunar surface structure study, and experimentally carry out lunar neutron radiation dose, neutral Atomic and other lunar environment research. In addition, the lander is also equipped with a lunar biotech test load. The No. 4 mission provides opportunities for Chinese and foreign scientists to explore space.
　　
　　Scientists believe that the back of the moon is more ancient than the front. The material composition and geological age of the von Carmen crater is representative and valuable for studying the early history of the moon and the solar system. The back of the moon is also a rare quiet place that shields the radio signal interference from the Earth. The low-frequency radio astronomical observations can fill the gaps in the low-frequency observation section of the radio astronomy field, providing the possibility to study the sun, planets and extrasolar objects. It will also provide important information for studying the origin of stars and the evolution of nebulae. Based on this, China National Space Administration is willing to cooperate with space agencies, space science research institutions and foreign space science enthusiasts from all over the world to explore the mysteries of the universe.
　　
　　Subsequently, the No. 4 detector will pass the relay communication link of the “Bridge Bridge” relay star, and under the ground control, the equipment working mode adjustment and other work will be carried out, and the lander and the patrol device will be separated."

http://www.cnsa.gov.cn/n6758823/n6758838/c6805034/content.html

This image is the image of the back of the moon on the south side of the landing site taken by the 着4 Lander Surveillance Camera C. The patrol will head toward the surface of the moon in this direction.

This image is an image taken by the camera when the 嫦娥4 detector is powered down.

This image is an image taken by the camera after the soft landing on the back of the Moon 4 detector.

http://www.cnsa.gov.cn/n6758823/n6758838/c6805034/content.html

Additional articles

"This isn't the first time China has landed on the moon. In 2013, Chang'e-3 successfully touched down on Mare Imbrium, a huge lava plane on the moon's surface. But until now, China has never explored the moon's mysterious dark side. No one has.

That's actually why it's called the "dark side". It's not hidden from the sun. It's hidden from our view. That's because the Earth and moon are in what's called synchronous rotation. Which means every time the moon rotates once on its axis, it also completes one orbit around the Earth."

https://www.businessinsider.com/china-first-land-on-far-side-moon-change-4-2019-1

"China has released photos of the dark side of the moon from its successful mission to become the first country to land a spacecraft on the moon's far side.

Photos shared by China's National Space Administration show close-ups of the lunar surface captured in what was both a first in history and a win for China in its efforts to compete with the US and Russia in space exploration.

The images were captured by cameras on China's Chang'e 4 lunar probe, which landed on the moon at 10:26 a.m. on Thursday, according to CNSA."

https://www.businessinsider.com/photos-dark-side-moon-china-change-4-landing-2019-1

"China's Chang'e-4 probe touched down on the far side of the moon Thursday, becoming the first spacecraft soft-landing on the moon's uncharted side never visible from Earth. The probe, comprising a lander and a rover, landed at the preselected landing area on the far side of the moon at 10:26 a.m. Beijing Time (0226 GMT), the China National Space Administration announced."

http://www.xinhuanet.com/english/2019-01/03/c_137716841.htm

"The landing area is the Von Karman Crater, named after a Hungarian-American mathematician, aerospace engineer and physicist, within the Aitken Basin. The area was intentionally selected after much consideration.

"When discussing the Chang'e-4 mission, we thought we should attach more creativity and functions to it, enabling it to do more challenging things," said Wu Weiren, chief designer of China's lunar probe program.

The far side of the moon was not the only first at first. Some experts even considered landing on other celestial bodies, but it would have required great changes made for the probe.

As Chang'e-4 began as a backup for Chang'e-3, many of their components and parts were designed and manufactured together, which allowed little room for changes, according to Sun Zezhou, chief designer of the Chang'e-4 probe, from China Academy of Space Technology.

Since the moon's revolution cycle is the same as its rotation cycle, the same side always faces the earth. The other face, most of which cannot be seen from Earth, is called the far side or dark side because most of it is uncharted.

"The rugged terrain of the moon's far side has made the landing much more risky than on its near side. However, more accurate landing technology is needed in the future," Sun said.

"For example, if we want to send detectors to the moon's bumpy polar regions and descend them on a relatively small area with permanent sunshine, it will demand very high landing precision," he explained.

"If we want to build a scientific research station on the moon, we will need to land multiple probes within the same area so that they can be assembled easily into a complex, which requires even greater landing accuracy," he said.

"So solving the challenges of the Chang'e-4 mission can lay the foundation for the following lunar exploration and future landing on other planets," he noted. "We hope that we will have the capacity to get to the whole moon and even the whole solar system in the future to support our deep space scientific explorations." "

http://www.globaltimes.cn/content/1134485.shtml