Just now, Chang'e 6 successfully launched!
The goal of Chang'e 6 this time is to travel to the far side of the moon, collect lunar samples, and bring them back to Earth. This will mark the first human mission to conduct sampling on the far side of the moon. So, what's different about "digging" on the moon's far side? What are the new challenges this time? Today, let's talk about the task of digging on the far side of the moon.
Humans have actually dug on the moon many times
Even today, some people still believe that the moon is hollow. If it is hollow, then it's likely a giant structure designed and built by aliens to monitor our Earth. Hey, Hollywood really knows how to ride the hype - if you've seen the movie "Moonfall," you know what I'm talking about.
It sounds absurd, right? But why do some people believe it? It's simple - because the moon is still mysterious, especially its far side. That's why in recent years, lunar missions from various countries have made the far side a primary target. And our Chang'e 6 mission is taking a big step by directly sampling and returning from the far side. They aim to help us understand the moon better.
In fact, this is not the first time we've dug on the moon. At the end of 2020, Chang'e 5 successfully carried out a mission almost identical to this one, except that time it landed on the near side of the moon.
That was China's first lunar soil excavation, but not the world's first. Including Chang'e 5, humans have dug on this closest natural satellite of ours ten times: NASA's Apollo manned moon landing program in the last century successfully landed six times, each time digging and bringing back a total of 380 kilograms of lunar samples, the most in quantity; then came the Soviet Union's three unmanned lunar sampling missions - Luna 16, Luna 20, and Luna 24, which brought back a total of 326 grams of lunar samples; finally, China's Chang'e 5 brought back 1731 grams of samples from the lunar surface.
Digging on the moon's far side turns out to be quite challenging
Sampling from the moon and safely returning seems not too difficult, but what's truly challenging is sampling and returning from the moon's far side. Why?
As the Earth's only natural satellite, the moon is both fortunate and unfortunate to be tidally locked to Earth, causing its rotation speed and revolution speed to gradually synchronize, ultimately resulting in the moon always "facing" Earth. We cannot see the moon's far side from Earth - it falls into our blind spot.
Similarly, besides being a blind spot visually, the far side of the moon is also a radio blind spot, which means a communication blind spot. Therefore, any probe that flies to or lands on the far side of the moon cannot establish direct contact with Earth. The wilderness on Earth is scary enough, let alone being on the moon.
What can be done to solve this dilemma? Imagine when you look in the mirror and want to see what's happening on your back. You ask someone to hold another mirror behind you, which serves the purpose of redirecting the light.
Similarly, to communicate with devices on the far side of the moon, we need a "mirror" precisely positioned on the lunar far side - that's where our Queqiao series relay satellites come in. Why are they called a series? Because up to now, two Queqiao satellites are already flying over the far side of the moon.
In 2018, Queqiao-1 successfully ensured the soft landing of Chang'e-4 and Yutu-2 on the lunar far side, marking humanity's first journey to the far side of the moon. Then in March this year, Queqiao-2 took a step ahead of Chang'e-6, arriving early over the lunar far side with upgraded equipment to support all activities of Chang'e-6.
So you see, we've been to the far side of the moon, brought back soil, and now with multiple generals watching from above, do we lack the confidence to create another first? We are fully confident!
How to Dig Soil on the Far Side of the Moon?
So, how will Chang'e 6 actually dig soil on the far side of the moon? To understand this, let's take a look at Chang'e 5.
Apart from their destinations, these two missions are almost identical in terms of their system components – both consist of an orbiter, a returner, an ascender, and a lander, weighing a total of about 8.2 tons.
Once in lunar orbit, they will work together as follows:
The lander will perform a series of descent maneuvers, powered descent, and attitude adjustments before making a soft landing near the Apollo crater in the South Pole-Aitken Basin on the moon. It will then use a shovel and a drill to collect lunar soil samples and rocks from the surface and subsurface, placing them in containers on the ascender. The baton is then passed to the ascender, which will lift off from the moon's surface after the lander completes sample collection, rendezvous with the orbiter returner combination, and dock.
The samples will then be transferred to the returner. Once this task is completed, the ascender will depart, separating from the orbiter returner combination. After transferring the samples to the returner, the orbiter will carry the returner back to Earth. Upon reaching the designated location, the returner will be released, completing the orbiter's mission. The returner will then re-enter the Earth's atmosphere, making a controlled descent to bring back valuable lunar samples.
Wow, all the mysteries are hidden within these approximately 2000 grams of samples... Of course, not all mysteries will be solved.
Firstly, the Chang'e 6 mission is not just about digging soil on the moon's far side; the scientific instruments it carries can provide us with a wealth of new knowledge. Secondly, to truly understand the moon, one or two missions are not enough. However, at least through these soil samples from the far side of the moon, our understanding of the moon will undoubtedly be greatly enhanced.
So, what specific insights might we gain? Let's boldly predict:
Composition and Evolution of Lunar Soil: The geological environment on the far side of the moon differs from the near side. By collecting samples from the far side, scientists can study the composition, mineralogy, and geochemical characteristics of lunar soil. This helps in understanding the moon's evolutionary history and its relationship with Earth and other celestial bodies. The rocks and soil on the far side may contain older materials less affected by impact events, providing crucial clues about the early evolution of the solar system.
Internal Structure of the Moon: The geological structures and internal composition of the far side of the moon remain a mystery. Analyzing samples from this region can reveal the composition and properties of the moon's crust, mantle, and core, essential for studying planetary formation and evolution.
Magnetic Fields and Heat Flow on the Far Side: The distribution of magnetic fields and heat flow on the far side differs from the near side. Data from the returned samples will help scientists better understand the physical processes inside the moon, such as heat conduction and geomagnetic activity.
Impact History of the Far Side: The far side of the moon is relatively flat with numerous impact craters. Analyzing samples from these craters can provide insights into the impact history of the far side and its effects on the lunar surface and geological structures.
Besides these, the Chang'e 6 mission also carries payloads and satellite projects from countries like France, the European Space Agency, Italy, and Pakistan. Therefore, in promoting international cooperation and expanding human knowledge of the moon, Chang'e 6 can make significant contributions.
After learning all this, are you, like me, already looking forward to the soil samples from the far side of the moon?
