As is often the case in Chinese space, there was no announcement. It was known that the Chang’e-5 mission would leave for the Moon before the end of November, to take samples there and then bring them back to Earth, but no precise date had been officially given. It was by seeing the Long March-5 rocket coming out of its hangar on Tuesday, November 17, then being moved to its launch pad at the Wenchang space base, that the world became aware of the imminent takeoff. This took place on Monday, November 23, at 9:30 p.m. French time.
Author of several books on China’s space adventure, Philippe Coué believes that “The purpose of the mission is above all technological, as with most Chang’e missions. It’s about showing that you have mastered the techniques. The steps are taken one after the other: I learned to circle the Moon with the Chang’e-1 and 2 orbiters, I learned to land and to roll a rover with Chang’e -3 and 4. And now I’m going to the next level, I’m learning to come back from the Moon ”.
On closer inspection, Chang’e-5 is nothing more than a scaled-down Apollo mission – but without humans on board. A service module transports a space train made up of three other elements. First of all a lander, similar to that of the two previous missions. Its robotic arm will collect soil samples, the famous powdery lunar regolith, and a drill will take cores up to 2 meters deep. The “harvests” will be stored in the second element, a small so-called lift stage, placed on the lander. It will tear itself away from lunar gravity to join the service module which remained in orbit.
This ascent and meeting around the Moon constitute the crucial points of the mission, two technical challenges that the Chinese will try to meet for the first time. Once the stowage has been completed, the samples (approximately 2 kg) will be transferred to the third element, the re-entry capsule into the Earth’s atmosphere, already tested in 2014. Then we will have to travel the way back. If all goes well, in a few weeks the capsule will land somewhere in Inner Mongolia.
Help for dating
The scientific goal of the mission is not negligible, which is coupled with a symbolic aspect: to become the third country to bring back lunar samples, after the United States and the USSR – the Soviet probe Luna-24 was the last , in 1976, to do so. A specialist in lunar and Martian geology, Jessica Flahaut, from the Center for Petrographic and Geochemical Research (CRPG) in Nancy, worked with Chinese researchers to determine an interesting “target”. The area planned for the landing is wide, “A large box several hundred kilometers long located in the Ocean of Storms”, the largest of the lunar seas. The terms “seas” and “ocean” obviously do not refer to vast expanses of liquid water, since this does not exist on the Moon, but dark basalt plains that ancient astronomers have taken for. seas.
You have 54.47% of this article to read. The rest is for subscribers only.