Because it is home to the deepest impact crater on our satellite, the South Pole Aitken Basin (SPA). “The asteroid that created it was so large that it probably brought rocks from beneath the lunar crust to the surface,” says Ed Cloutis, a geologist at the University of Winnipeg who is analyzing rocks moons brought back by Apollo. “It will allow us to better understand the formation of the Moon. »
If the impact didn’t bring rocks from beneath the crust to the surface, it means the crust is thicker than expected, and models of how the moon formed will need to be revised, Cloutis said.
The material brought to the surface by the impact that created the SPA basin was located more than 80 km deep, twice as deep as the second largest lunar crater. The SPA basin is the largest known impact crater in the Solar System, with a diameter of 2500 km. It was created more than four billion years ago.
Probably not, says Mr. Cloutis. “Maybe if we find water easily accessible, but the disadvantages of communication delays are very great. »
“Even though the Moon has no atmosphere, many things can change the appearance of its rocks,” says Cloutis. There are asteroids, the solar wind. With the samples, we began to separate the effects of geology and these factors. »
None are on the menu. NASA proposed one 25 years ago, identical to Chang’e 6. In 1962 NASA’s Ranger 4 impactor crashed into the far side, but failed to send back any scientific data.
Because it is always opposed to the Earth. Moreover, the hidden side of the Moon receives light from the Sun and is not always dark.
“Chang’e 6 is the most complicated robotic lunar mission ever carried out by any country,” says Brian Harvey, an Irish political scientist who has published several books on China’s space program. Communications must be relayed by lunar orbiters, which increases the transmission delay, notably complicating the moon landing.
Chang’e 6 was not part of China’s lunar program, Harvey says. But after the success of Chang’e 4, which landed in the SPA basin in 2019, it was decided to use a spare lander from the Chang’e 5 mission (which brought back lunar samples in 2020) to bring back samples from the far side, during the Chang’e 6 mission.
Probably because no country had done it, according to Mr. Cloutis. “The difficulty of the mission demonstrates China’s technical capability. »
Harvey adds that the Tianwen-3 mission, which is expected to bring back Martian rocks in 2030, will be relatively similar. This means that China could be the first country to bring back Martian rocks, because the mission to bring back Martian samples gleaned by the American rover Perseverance is currently in question because of its cost.
“Samples of Chang’e 5 have been offered to researchers from all countries,” says Cloutis. I plan to ask for and receive some. »
This is a possibility raised by the big boss of NASA in 2023 in Politico magazine, where he spoke of a “race to the Moon”. Bill Nelson cited as an example the Chinese territorial claims in the South China Sea.
“He knows the importance of having political support from Congress and the funding that comes with it,” Harvey said. “China announced its space program through 2050 as early as 2009. They’re very transparent.”
Mr Harvey doesn’t think China is in a race to the Moon. A better comparison, he said, would be the cooperation of several countries, including China, in Antarctica.
