China’s Moon Mission Was About More Than Rocks

If everything goes according to plan, China will soon become the third country behind the United States and the Soviet Union to successfully return a sample of lunar material. Their Chang’e 5 mission, which was designed to collect 2 kilograms (4.4 pounds) of soil and rock from the Moon’s surface, has so far gone off without a hitch. Assuming the returning spacecraft successfully renters the Earth’s atmosphere and lands safely on December 16th, China will officially be inducted into a very exclusive club of Moon explorers.

Of course, spaceflight is exceedingly difficult and atmospheric reentry is particularly challenging. Anything could happen in the next few days, so it would be premature to celebrate the Chang’e 5 mission as a complete success. But even if ground controllers lose contact with the vehicle on its return to Earth, or it burns up in the atmosphere, China will come away from this mission with a wealth of valuable experience that will guide its lunar program for years to come.

In fact, one could argue that was always the real goal of the mission. While there’s plenty of scientific knowledge and not an inconsequential amount of national pride to be gained from bringing a few pounds of Moon rocks back to Earth, it’s no secret that China has greater aspirations when it comes to our nearest celestial neighbor. Starting with the launch of the Chang’e 1 in 2007, the Chinese Lunar Exploration Program has progressed through several operational phases, each more technically challenging than the last. Chang’e 5 represents the third phase of the plan, with only the establishment of robotic research station to go before the country says they’ll proceed with a crewed landing in the 2030s.

Which helps explain why, even for a sample return from the Moon, Chang’e 5 is such an extremely complex mission. A close look at the hardware and techniques involved shows a mission profile considerably more difficult than was strictly necessary. The logical conclusion is that China intentionally took the long way around so they could use it as a dry run for the more challenging missions that still lay ahead.

Luna’s Legacy

Model of Luna 16 at the Museum of Cosmonautics

While most people associate Moon rocks with the Apollo program, the Soviet Union also conducted a series of successful robotic sample return missions during the 1970s. The three Luna missions only brought back a small fraction of the material that NASA did with their far larger and more ambitious crewed vehicle, but they proved that even with the relatively primitive technology of the era, lunar sample return could be done at a far lower cost and without risk to human life.

It stands to reason that replicating the Luna missions of the 1970s would still be the fastest and cheapest way to return a sample from the Moon. By today’s standards, the sensors, cameras, and communications equipment used on those early landers are absolutely archaic. Modern materials and battery technology would also allow for a far lighter craft than was possible 50 years ago, though the 5,727 kg (12,626 lb) launch mass of the Luna 16 still would have been within the payload capacity of China’s Long March 5 booster.

Calling it easy would certainly be a stretch. After all, modern technology and materials alone weren’t enough to prevent Israel’s Beresheet lander from crashing into the lunar surface. But China had already placed several robotic craft on the Moon, so adding a Luna-inspired return stage to the Chang’e 5 lander would have been the most expedient way to achieve their goals. Instead, they did something very different.

Echos of Apollo

When referring to Chang’e 5, we aren’t really talking about a single spacecraft, but a “stack” of several distinct vehicles that each have a specific role. Once the craft were in orbit around the Moon, the lander separated and descended independently to the surface. Soil and rock samples were then loaded into a smaller ascent vehicle mounted to the top of it. This diminutive craft took off from the Moon, leaving the lander behind, and docked with the service module that had remained in orbit. The samples were transferred to the orbital module, which then detached from the ascent vehicle and used its engine to leave lunar orbit and begin the return leg of the journey. In the end, only a small capsule will actually make it all the way back and land on Earth.

LOR proponent John Houbolt in 1962

If that sounds familiar, it’s because this is the same mission architecture used during the manned Apollo missions. Known officially as Lunar Orbit Rendezvous (LOR), this concept was selected by NASA because it allowed for a much smaller booster than would have been required otherwise. A single spacecraft capable of flying to the Moon, landing, and then returning to Earth would be extremely heavy; largely because the propellant necessary for the return to Earth would be nothing more than dead weight on the trip down the lunar surface and back.

With the “nesting doll” LOR approach, each subsequent phase of the mission is accomplished by a smaller and lighter craft. The downside is that it’s operationally far more complex, requiring two spacecraft to rendezvous and dock in lunar orbit. For NASA, that meant years of additional research and development had to take place before Apollo could ever head to the Moon. This lead directly to Project Gemini, a series of missions used to develop the navigational and docking techniques that would eventually be used during Apollo’s lunar rendezvous.

Little is currently known about China’s plans in regards to human exploration of the Moon, but it stands to reason they’ll use the same tested LOR architecture that NASA demonstrated during Apollo and will continue to use during the Artemis program. By testing automated rendezvous and docking techniques during the robotic Chang’e missions, China could potentially avoid spending the time and money required for their own crewed Gemini-style program.

Practice Makes Perfect

The crew of Apollo 10 had the honor of performing the first rendezvous and docking in lunar orbit as part of the “dress rehearsal” for the eventual landing made during the Apollo 11 mission, but Chang’e 5 marks the first time such a feat has been accomplished by a robotic craft. While remotely operated vehicles have previously docked in geostationary orbit, the unique challenges of performing such a delicate operation while in orbit around another body make this a considerable technical achievement.

The Chang’e 5 orbiter and ascent vehicle meet in orbit.

Which is why China made sure to get some practice runs in first. The Chang’e 5-T1 mission was launched in 2015 to demonstrate some of the techniques that would be required to eventually return from the Moon. This included testing the sample capsule’s ability to safely reenter the Earth’s atmosphere and performing several simulated docking maneuvers.

Even though the vehicle only had a virtual partner to practice with, this experiment could be seen as analogous to the later Gemini missions, which had astronauts dock their spacecraft with the unmanned Agena Target Vehicle while in low Earth orbit. When it came time for the real thing, the rendezvous and capture of the Chang’e 5 ascent vehicle went perfectly on December 5th. There’ll be another opportunity to gather data on autonomous lunar docking during the Chang’e 6 mission to the Moon’s south pole as well, which is currently expected to happen by 2024.

It’s still too early to say how much of an impact these robotic practice runs will have on their crewed counterparts in the 2030s, but one thing is for sure: China now knows a lot more about lunar rendezvous and docking than the United States did before the Apollo program.

67 thoughts on “China’s Moon Mission Was About More Than Rocks

      1. Especially one person named Sasin. He spent 70 millon pln on printing cards for elections which did not happen. After several such failures this year, he was voted as first entry in a contest for youth word of the year. But because such entry was against rules, the contest was cancelled. Therefore in perfect summary of this year and our government, he won a contest which did not happen.

  1. Who gives a flying duck? Rotten communist govenment was behind the first man (and woman) in Space and rotten capitalistic government was behind the first man on the Moon. Both still great achievements.

    1. Sounds like an excellent way for a government (or even the private sector) to spend money. Puts a lot of people to work to make it happen. It increases our knowledge, and usually technology. Seems to me a win win.

        1. You only need to look at the article for evidence of one of the reasons why the US has crippled it’s output of manufacturing for the globe. See those olde fashioned units (Roman pounds, feet and miles) in parenthesis? Those are there for the USA ONLY. We are a special needs nation because we can’t/won’t embrace international standards and join the rest of our global family by embracing the international system of weights and measures. It’s utterly foolish. Nothing on earth is built with the inch/pound anymore. We need to be smarter and more connected to the world, not isolated from it.

    2. Haven’t you learned anything about the pointlessness of life?

      The point of the pointlessness of life, is that you get some 60-90 years of time to do all sorts of random pointless stuff in order to create some point to your life yourself.

      Ergo, life can only be judged in retrospect, and if it turns out to have been pointless, you failed at creating a point to your life.

      The easiest way of getting a pointless life, is to reject all ideas and pursue nothing.

    3. Not a “pointless act”! Let’s see you do the same thing on any small budget. It took years to get everything together to bring back Moon ROCKS, NOT DIRT. You must be incredibly behind times to not realize what science advancements had to be made for that trip alone, now we aim for Mars! “It was impossible to go to the Moon”, in my youth, now it just takes planning. ‘Nuff said!

  2. Moon missions are especially cool cause they happen in real time. you don’t have to wait months or longer for one stage to happen and then wait more after that.
    this whole mission went down excitingly fast.
    we need more of this.
    much more

        1. Earth has water and life causing great variety. The moon is extremely boring in comparison. You might find a rock that has higher/lower amount of some element, or a different crystal structure. Mildly interesting, but not a big deal.

          1. Fundamentally untrue. Lunar geology is very varied. That is why you can see features on the lunar surface. The rocks themselves tell stories of the formation of the planets and the moon, the solar activity and the meteorites that pummel the moon. Don’t go round thinking your ignorance in a subject is representative of how much can be learned.

      1. Well, except for the fact that most of the Moon rocks humanity has are locked up by NASA. China bringing some home will allow more scientists and researchers than ever before to have access to them.

        Of course, they’ll probably all be Chinese researchers. The “team sport” mentality goes both ways, unfortunately.

        1. You can already buy Moon Dust 0.2 Grams on Amazon. I’m holding out for 19 grams. It will be just like lithium batteries; if you want 9900mAh you have to keep your eye out and buy fast!

          Everybody knows NASA locks their vault, but everybody also assumes China unlocks their vault. Researchers will need to wait for India to bring back samples and create testing benchmarks before they can even publish their results outside China.

          North Korea should do them one up and after a rocket launch they can dump some Mercury stones on the market. Purest Mercury, 99.9%, only $9.99. 0.468 grams! Best deal or monkey back.

        1. If a couple-gram vial, double-bagged, held within a NRL facility counts as accessible, I’ll eat my words.

          “All told, the six Apollo missions collected 2,196 samples, which weigh 842 lbs. (382 kilograms) under Earth’s gravity — nearly as much as a horse. ”
          “NASA still holds onto about 85% of the moon rocks collected by astronauts during the Apollo program.”

          342 kg of 382 kg have never left their Houston facility. Trace amounts have been used for science and museums.

          1. “Trace amounts have been used for science and museums.”

            Wow so 40,000 milligrams of moon rock is a “trace amount”! Do you put “trace amounts” of salt on your steak?

          2. “If a couple-gram vial, double-bagged, held within a NRL facility counts as accessible, I’ll eat my words.”

            Eat up, you don’t even have a use case for getting that close.

            A child can look at those rocks, and extract huge amounts of value from it. If you failed to do so, it is not because you had a more demanding use case; you merely chose to decide that the level of access appropriate for rare items in a large world is not good enough. But it is more than accessible enough for children, and those children manage to extract so much more use from the rocks than you do that they are clearly the experts between you.

            It isn’t a food, and it doesn’t have a magical texture. Touching it will change it. Having a rock that 100 million people touched, it will just be an Earth rock, full of the oils of Earth creatures, it will be nothing like a moon rock anymore.

          3. They all get used for science. You can do it there at the facility, or borrow them. Maybe by “used for science” them mean used up. As in dissolved in reagents or vaporized in flame spectroscopy, etc. And it turned out you really don’t need very much when it is all the same. They are rocks. And we know how to analyze rocks. All the cool minerals on Earth are from water and heat and pressure and plate tectonics with vulcanism sucking sediments down and thrusting them up. But not on the Moon.

          4. Taking the salt analogy seriously: the last Apollo flight was in 1972, about 17,500 days ago. The recommended daily salt intake is 1.5 gm / day. That’s 26.25 kg since the last moon rock was collected. Order of magnitude. (I’m not that old, and I’m also not the only person in the world consuming salt.)

            I guess, for the sake of less inflamatory comments, I should have made my point more clearly: NASA is sitting on the majority of the moon rocks, they’re kept in storage in a facility where they are essentially underutilized, and it’s a large institutional problem b/c nobody has any clear incentive or directive to make them available to the public. And I presume there’s also not much demand for them from geologists. So they sit there.

            I have spoken with someone close enough to the moon rocks, and he mentioned that it’s a problem for NASA — they have them, they don’t want to contaminate them, the government can’t officially own them because they’re part of a celestial body with no ownership, and so the moon rocks fall into a strange legal/bureaucratic grey zone of inaction.

            Some amount of the collection has been used for science, and granted to museums. It’s a small percentage.

            I hope these comments don’t come across as either anti-bureaucracy or anti-space-research. I worked for eight years in DC in the bureaucracy, and was nothing if not impressed by the dedication, honesty, and brains of my colleagues. That the institutions are very conservative (read: slow, not politically conservative) is appropriate, because continuity is important for running the nation, but also infuriating when you see something that should be changed.

            Without a strong driver for moon rock liberation, the easiest course of action is the status quo. It would be awesome if someone with enough clout in NASA, or someone who could persuade someone with the clout, took on the moon rocks as a passion project.

            This bureaucratic inaction was most evocatively summarized (for me) by that last scene in Indiana Jones. The fact that the vast majority of moon rocks are literally sealed up in an inaccessible vault is just life imitating art.

          5. Elliot, you describe the problems with the legal and bureaucratic status of the moon rocks. I think it is not the worst to conserve them, until somebody has a good reason to touch them, use them or do something with them, e.g. a research project. If I need just a paper weight, a normal earth rock is enough :-)

          6. Universities that have good reason to use them can and do borrow samples all the time, or visit the facility that has the equipment to protect the rocks already there. and not just US universities. The controls in place are important to stop the rocks all disappearing to be desk ornaments in private collections. Remember that only recently was a core sample generously donated to Stonehenge from the family of the selfish chap who decided having it on his desk was better than it being used for the science they had used to justify drilling into an ancient monument. If genuine Apollo moon samples showed up on ebay, the price collectors would pay would be too tempting and soon there would be none left for science.

            Given much of the scientific interest is that the rocks haven’t reacted under atmosphere or sunlight (for the centre of rocks), the double bagged approach is very sensible. The reason smaller craters on the moon are bright is that sunlight and particles from solar wind are enough to blacken the rocks. They aren’t just inanimate, if you sit them on your lab bench they are ruined.

  3. So you assert that it’s different here in the US, instead of “forced labor” we have no social safety net so that people have no food and no health care if they are unemployed, and somehow it is so much more humane to let people starve out in the open than it is to put them in camps. Yes indeed ride that moral high horse!

    1. What kind of a human being thinks labor camps are an improvement over the USA’s welfare system?!? No wonder you sign as “X”.
      It may be a somewhat broken system, but the suggestion that we should treat people like cattle is repulsive and disgusting. How can you look in the mirror while harboring such sick thoughts?!?

      1. What kind of human being projects their opinions onto others? What kind of human can’t tell the difference between an observation and an opinion?

        ” the suggestion that we should treat people like cattle is repulsive and disgusting. ” What kind of human invents lies like that? I never said anyhing even remotely resembling that. Yes indeed you are a master of projection.

        1. Oh. You don’t know about the concentration camps?

          Are you a 1930s German, pretending you don’t know, or are you living in a place where it is illegal to view the reports?

          Concentration camps. That’s what you’re getting morally relativistic about. Concentration camps. To you it is just “opinion.”

    2. If having to get your free food from a charity is “no food,” that is not a political problem but a personal philosophical problem.

      The US is swimming in food, and access to calories is not actually a serious challenge for the poor unless they’re drug addicts who are too dysfunctional to show up on the right day.

      Food access for the poor might even be easier in the US; but we’ll never know, because if a Chinese person tries to do that study they’ll be arrested and their work destroyed. They’re not even allowed to talk about what services are available in other places.

      Look at photos of day laborers in any Chinese city. There are clear signs of chronic food insecurity visible in their bodies. Consider this; many others never returned from the city, and even more were not privileged enough to be allowed to be a day laborer in the city. And so they remained in their village. Where only reports that present the country in a good light are allowed to even be discussed, much less published.

      It is really, really hard to find a starving person in the US. Certainly not in homeless camps. You have to find people with no social network, who don’t leave home, and won’t accept help.

  4. “I’m hoping that the Chinese government will bear the costs that the other 7 billion of us will have to pay to clean up their stupid mess, but I’m not going to hold my breath.”

    Why do you hope for impossible things? Do you really expect the chinese to raise the dead? Too many zombie movies on netflix? While you are at it, maybe the US government should compensate the natives, maybe we can make a list of everyone in history who has been screwed over and make sure they are fairly compensated.

  5. China cleaned up their mess rapidly. That’s more than I can say for some countries, especially the US, who said it was a hoax, would be gone by April, and did basically nothing to prevent its spread. That’s on you, not China.

  6. Totally, like that other country that paid the rest of the planet for releasing the Spanish flu. Where were the very first observations of illness and mortality documented of that, which country was it ?

  7. “I worked for eight years in DC in the bureaucracy, and was nothing if not impressed by the dedication, honesty, and brains of my colleagues. ”

    Having worked around much of the same sort of folks for 15 of my nearly 40 year career I think this is one of the funniest statements I’ve ever read. There’s a very good reason government employees have the reputation they do.

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