China is about to launch the first mission.
The Chang'e-4 mission will see a static lander and rover touch down in Von Kármán crater, located on the side of the Moon which never faces Earth.
Rocket from Xichang Satellite Launch Center at 6:30 pm GMT.
Moon rock and soil to Earth.
The day will not be until early January, when the probe will descend on thrusters and touch on the rugged terrain.
Von Kármán crater is from the Moon and the South Pole-Aitken Basin. This was probably formed by a giant asteroid impact billions of years ago.
The landers will characterize the region's geology and the composition of rock and soil.
Because of a phenomenon called "tidal locking", we see only one "face" of the Moon from Earth. This is because the Moon takes just as long as it rotates on its own axis as it takes to complete one orbit of Earth.
Though it is referred to as the "dark side", this face is also illuminated by the Sun and has the same phases as the near side; "dark" in this context simply means "unseen".
The far side looks rather different. It has a thicker, older crust that is pocked with more craters. There are also few of the "sea" – dark basaltic "seas" created by lava flows – that are visible on the near side.
The powerful impact that created the South Pole Aitken Basin may have been punched through the crust down to the Moon's mantle layer. Chang'e-4's instruments could examine whether this was the case, shedding light on the early history of our only natural satellite.
The "radio environment" on the far side, on the radio side of the radio.
The static lander will carry a 3kg container with potato and arabidopsis plant. The "lunar mini biosphere" experiment was designed by 28 Chinese universities.
"We want to study the respiration of the seeds and the photosynthesis on the Moon," Liu Hanlong, chief scientist of the experiment and vice president of Chongqing University, told the state-run Xinhua news agency earlier this year.
Xie Gengxin, chief designer of the experiment, told Xinhua: "We will keep the temperature in the 'mini biosphere' within a range of 1 degree to 30 degrees, and we will be able to control the humidity and nutrition. the natural light on the surface.
They have to send data back via satellite relay named Queqiao, launched by China in May this year.
The probe's design is based on its predecessor, Chang'e-3, which deployed landing craft to the Moon's Mare Imbrium region in 2013. However, it has some important modifications.
China's lunar ambitions
The lander is carrying two cameras; a German-built radiation experiment called LND; and a spectrometer that will perform the low-frequency radio astronomy observations.
The rover will carry a panoramic room; radar to probe beneath the lunar surface; an imaging spectrometer to identify minerals; and an experiment to examine the interaction of the solar wind with the lunar surface.
The program is part of a larger Chinese program of lunar exploration. The first and second Chang'e missions were designed to gather data from orbit, while the third and fourth were built for surface operations.
Chang'e-5 and 6 are samples return missions, delivering lunar rock and soil to laboratories on Earth.
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