For the first time, a spacecraft will land on the far side of the moon. A technological challenge for the Chinese who innovate by performing a feat that neither Russia nor the United States had yet undertaken.
China has launched this Saturday an exploration module that must land on the far side of the moon, a world first that should strengthen Beijing's space ambitions.
The vehicle dubbed Chang'e-4, named after the goddess of the moon in Chinese mythology, was launched by a Long March 3B rocket from the Xichang launch center in southwestern China on Saturday. 2:23 am local time (18:23 GMT Friday), announced the official news agency China News.
Beginning of exploration in January
This is the beginning of a long journey for the Chinese machine, which should be around January 1 to study this unexplored part of the Moon and conduct scientific experiments.
Unlike the face of the Moon closest to the Earth, which is always facing our planet, no probe or exploration module has ever touched the ground on the other side.
The hidden face is mountainous and rugged, dotted with craters, while the visible face offers many flat surfaces to land. It was not until 1959 that the Soviets took the first pictures.
A major challenge for the Chinese
Chang'e-4 will be "the first probe of humanity to land on the far side of the moon and explore it," said the head of the mission, He Rongwei, quoted by the daily Global Times, published in Chinese and English. "This mission is also the largest space exploration project in the world in 2018," he said.
"For the last ten or twenty years, China has been systematically following the steps that America and the Soviet Union had taken in space exploration in the 1960s and 1970s," said Jonathan McDowell, astronomer at the Harvard-Smithsonian Center. for astrophysics. "This is one of the first times that the Chinese have undertaken something that no one else has done yet . "
For years, China has been preparing for this particularly difficult operation from the technological point of view.
One of the major challenges is to be able to communicate with the lunar robot: the hidden face is always oriented in the opposite direction to the Earth, there is no direct "line of sight" to transmit the signals, except to install a relay.
In May, China launched a satellite called Queqiao, positioned in lunar orbit to relay orders and data exchanged between the earth and the module.
Extreme temperatures
During the lunar night, which lasts for 14 Earth days, temperatures fall to -173 degrees Celsius, and during the lunar day, also equivalent to 14 Earth days, they can reach 127 degrees Celsius.
And to compound the difficulty, the Chang'e-4 was sent to a region of the South Pole of the Moon, the Aitken Basin, whose terrain is particularly complex and steep, according to Chinese state media.
The equipment must, in particular, conduct studies on radio low frequencies, mineral resources and the cultivation of tomatoes and other plants.
This is the second time that China has sent a craft to explore the lunar surface after the Yutu (Jade Bunny) in 2013, which remained active for 31 months.
Collection of samples
Beijing is already planning to launch a Chang'e-5 next year to collect samples and bring them back to Earth.
China invests billions in its space program, led by the military. It places satellites in orbit, on its behalf (earth observation, telecommunications, Beidou geolocation system) or for other countries. She also hopes to send a robot on Mars and humans on the moon.
Beijing unveiled in November a replica of its first major space station ( "Heaven Palace" ) to be assembled around 2022 and succeed the ISS, the International Space Station.
The ISS associates the United States, Russia, Europe, Japan and Canada, but his retirement is scheduled for 2024.