Our natural satellite has not attracted so much light for fifty years. Because after the “big step for humanity” of 1969, the conquest of space almost stopped the “small steps” towards the eclipsed Moon. But in recent years, the Space Race has reconnected with its first love and China, a new leading player, is not left behind. This is evidenced by the new Chinese space mission Chang’e 6, which is scheduled to take off this Friday at 9:30 a.m. (French time) from the Wenchang spaceport, in the province of Hainan.
A technical challenge and, above all, a historic step in the discovery of this rocky star, while the mission must land on the hidden side of the Moon. Because the star “has a gravitational lock and always presents the same face to the Earth”, explains Olivier Sanguy, responsible for space news at the Cité de l’Espace in Toulouse. China was the first country to land a machine on this far side, in 2019. Then, in 2020, the Chang’e 5 probe brought back lunar samples, a first in more than forty years. But this Chang’e 6 mission, which must last 53 days (a little more than double that of the Chang’e 5 mission) is even more ambitious.
Samples from the far side of the Moon
The moon landing is scheduled for June 2, with the craft first having to be placed in lunar orbit to prepare for its descent and mission. After this moon landing, “a robotic arm will take samples and dig up to two meters deep,” declares Olivier Sanguy. “This is a great first,” says Estelle Moraux, lecturer at the Institute of Planetology and Astrophysics in Grenoble, who specifies that “two kilos” of samples must be brought back to Earth. “From a scientific point of view, this is completely new because we will have access to a different geology of the Moon. The far side receives many more meteorite impacts [que la face visible] and we will be able to analyze these materials without deterioration,” explains the researcher at the Grenoble university space center.
“ The Moon is like a piece of Earth torn off more than four billion years ago and then put in the fridge! » »
On Earth, when a meteorite enters the atmosphere, it burns, melts and, therefore, changes. Some meteorites completely disintegrate before hitting the ground, while others are only a twentieth of their original mass. The samples brought back by Chang’e 6 will be all the more precious because by examining them, “we also study the history of our planet, because the Moon is like a piece of Earth torn off more than four billion years ago. years then put in the fridge! », illustrates Olivier Sanguy.
A real “technological challenge”
The Chang’e 6 mission is therefore revolutionary for our understanding of Earth and Space, but it also represents a considerable technical challenge. “It’s already difficult to land on the Moon, so on the far side…” summarizes Olivier Sanguy, listing the numerous lunar landing missions that have failed, from India to Russia. “The terrain is much more uneven on the far side, it is not easy to find a place that is approximately flat to land,” explains Estelle Moraux, who recalls that “several probes found themselves unbalanced on the Moon and lost contact with Earth” recently.
In addition, “for a mission on the far side, it is not possible to communicate the direction, you need a relay satellite which will triangulate,” explains Olivier Sanguy. “It’s a technological challenge. This is the first time that a mission has really landed on the far side of the Moon, where no connection is possible with the Earth,” adds Estelle Moraux.
A “necessary step” before March
After several missions linked to the Moon, Beijing is therefore pushing the cursor even further with Chang’e 6. “China is very clearly displaying its Moon objective,” underlines Estelle Moraux. The head of NASA, Bill Nelson, also estimated in mid-April that the United States was now engaged in a space “race” with Beijing. The American Artemis 3 mission plans to land astronauts on the Moon in 2026. China has mentioned the same project for 2030. But the dates could get closer while Beijing is discreet about the progress of its space program and that Washington is suffering from delays and tensions over the financing of its projects.
“The Moon is a stopover before going to Mars. Space programs consider it a necessary step,” assures Estelle Moraux. “Artemis clearly displays an objective of “Moon to Mars”, from the Moon towards Mars”, adds Olivier Sanguy. Who adds with a smile: “I have always been told that women and men will be on Mars in twenty years, but I have been told that for forty years. »
Because yes, our natural satellite is an excellent training ground for one day setting out to conquer Mars. But only 384,400 kilometers from Earth, these lunar “trainings” remain incomparable to a Martian epic, while the planet is more than 55 million kilometers from us…