China is the first in the world to launch a landing mission on the far side of the moon. The launch of the Chang'e-4 automatic interplanetary station aboard the Changzheng-3B launch vehicle was carried out on December 8 at approximately 02:00 local time (December 7 at 21:00 Moscow time) from the Xichang cosmodrome (southwestern Sichuan province)). If all goes according to plan, the Chang'e-4 vehicles will go down in history as the first in the world to land on the far side of our satellite sometime in early January next year.
The Chang'e-4 mission consists of a stationary lander and a lunar rover, which face various scientific tasks, mainly aimed at exploring largely unexplored areas of our planet's natural satellite.
Launch of the Changzheng-3B booster from the Xichang Cosmodrome on December 8, 2018.
Where no one has ever been
The moon is in tidal grip on our planet. In other words, it takes a satellite almost the same amount of time to complete one revolution around its axis and around our planet. Therefore, from the Earth, we always observe only one side of our cosmic neighbor, that is, the so-called near. The far side of the satellite is always out of our field of vision. That is why this mission is of such great interest to everyone.
At the same time, being on the far side of the Moon will impede communication between the Earth and the lander and the rover - the Moon is a solid body, direct signals will be blocked.
View of the opposite side of the Moon and the Earth against its background (upper left part of the image). Photo taken during the Chang'e-5T1 space mission by the service module in 2014.
Promotional video:
To solve the problem, China launched the Quetqiao orbiting satellite in May this year. It is located behind the Moon at the L2 Lagrange point and will act as a repeater, transmitting and receiving information from the Chang'e-4 spacecraft and the Earth.
Most likely, the signals will come from the bottom of the Karman carriage - a 186-kilometer hole on the lunar surface, where, according to expectations, the network module and the lunar rover should. The crater is part of the South Pole Basin - Aitken - one of the largest impact formations in the solar system. From edge to edge, its length is 2500 kilometers.
Chinese lunar rover Yuytu, photographed by the Chang'e-3 lander in December 2013.
Lots of new scientific evidence
Within the framework of the Chang'e-4 mission, it is planned to use a whole range of scientific instruments. The lander is equipped with Landing Camera (LCAM), Terrain Camera (TCAM), low frequency spectrometer (LFS), and a neutron dosimeter (LND) provided by Germany. The Lunokhod has a panoramic camera (PCAM), penetration radar (LPR), a visible and near infrared spectrometer (VNIS), and a compact uncharged particle analyzer (ASAN) presented by Swedish scientists.
All this equipment will allow Chang'e-4 to study in detail the environment of the surrounding space. For example, the low-frequency spectrometer (LFS) will provide information about the composition of the lunar surface on the back of the satellite, and with the help of penetrating radar (LPR), scientists can learn more about the layered structure of the surface. This information will help you better understand how the far side of the moon differs from the one that is always directed towards the Earth. For example, huge basalt plains, called lunar seas, are more common on the near side of the satellite, but practically absent on its far side. By the way, don't call the other side the "dark side". In fact, it receives as much sunlight as the neighbor.
"Chang'e-4" also expects some radio astronomy work - the absence of radio interference from Earth on the reverse side will come in handy. The Queqiao orbiting satellite is also collecting astronomical data using the Low-Frequency Explorer tool, a joint development of the Netherlands and China.
A biological experiment is also planned with the help of the lander. There is a small closed ecosystem on board that contains silkworm eggs and tomato and Arabidopsis seeds. Scientists want to test whether these organisms can survive and develop on the lunar surface.
Throw to the moon
The Chang'e 4 mission is part of a larger Chinese lunar exploration program. In 2007 and 2010, the country sent Chang'e-1 and Chang'e-2 satellites to lunar orbit. In December 2013, the Chang'e-3 lander and the Yuytu lunar rover landed on the surface of the satellite's near side. Chang'e-4 was originally developed as a backup mission, but after the partial success of Chang'e-3, it was decided to launch it as a separate mission.
Chang'e-4 mission launch:
In October 2014, China launched the Chang'e-5T1 mission, during which a test vehicle was sent to fly around the moon, which returned back to Earth after 8 days.
The mission "Chang'e-5" is also being prepared. In its course, it is planned to collect samples of the lunar surface on the near side of the satellite and return them to Earth. It is currently under development. It was planned to launch it back in 2017, but decided to postpone it to 2019.
According to earlier statements by Chinese officials, the country is also planning to conduct manned missions to the moon, but the timing of these missions remains unclear. Most likely, it will not be soon. With regard to the manned program, China is now focused on the development and launch of a new near-Earth orbiting space station, which is scheduled to become operational in the early 2020s.
Nikolay Khizhnyak