Named after the Chinese Moon goddess, Chang’e is a lunar sample return space probe. Chang’e 5 is part of the Chinese lunar exploration program, and was set up by the Chinese space agency (CNSA). The space probe was developed and then built by China Aerospace Science and Technology corporation (CASC), a Chinese state-owned company, founded in 1999, that brings together most of the country’s research, design and manufacturing centers in the space sector. CASC is, in particular, in charge of the development of Long March rockets.
Approved in 2011, the Chang’e program contains Chang’e 1 and 2 which are orbiters and Chang’e 3 and 4 which are landers. The mission really began in 2014 when Chang’e 5 T1 was launched in order to test the reentry capsule and the various maneuvers in lunar orbit.
The proceeding of the mission
Chang’e 5 was launched on November 23, 2020 on board of the Long March 5 rocket. Chang’e 5 unit was composed of four modules: the lander, the ascender, the orbiter and the returner.
Once the space probe reached the Moon orbit, Chang’e 5 unit split in two parts: on one hand the lander and ascender that landed together on the surface of the Moon to collect samples, while, on the other hand, the returner and orbiter stayed into orbit. The landing site chosen was near Mons Rümker in Oceanus Procellarum, located in the northwest region of the Moon’s near side.
Then the second step was for the lander to collect samples of the Moon surface. And then, on December 3rd 2020, once the samples have been collected, the ascender separated from the lander and performed an automatic ascent to the returner and orbiter part that stayed into orbit. After docking, the ascender transferred the samples to the returner before falling back to the surface of the Moon.
Afterwards, the orbiter and returner part started their return to Earth. Once they were in Earth orbit, the returner separated and landed on the surface of Earth on December 16, 2020 in Inner Mongolia. The samples were collected and transferred to specialized sites for analysis.
The Chang’e mission is a technical achievement in itself but one of the main achievement was the success of the Lunar orbit rendezvous (LOR). The Lunar orbit rendezvous was a concept developed by Yuri Kondratyuk in 1919 to send humans to the Moon and then bring them back to Earth in the most economical way possible.
LOR is based on the following proceeding: for a mission to the Moon, we would send a main ship with a lunar lander. Once in orbit of the Moon, the lander would descend to the surface while the main ship remained in orbit. When the mission would be accomplished, the lander would take off from the Moon to meet and re-dock with the spacecraft. The next step would be to transfer either the crew, if it’s a manned mission, or samples into the spacecraft before landing again on the Moon while the main spacecraft returned to Earth.
The main advantage of this procedure is to save spacecraft payload. Because the main spacecraft would stay into orbit, the weight of the propellant necessary to return to Earth wouldn’t have to be carried to the Moon. The Chang’e 5 mission succeeded in making the first automatic Lunar orbit rendezvous in history. Before this process was used for the Apollo program but the maneuvers were carried out by the astronauts.
The scientific aims of the mission
The samples collected are important for our understanding of the geological history of the Moon since they are supposed to be “only” 1.21 billion years old, while other samples recovered during the Apollo missions were between 3.1 and 4.4 billion years old. The study of these samples could strengthen the hypothesis that certain areas of the Moon have undergone volcanic activity. Currently scientists estimate that volcanic activity on the Moon stopped 3.8 billion years ago, but many believe it may have lasted up to 100 million years ago in this region.
But on top of that, it is believed that this site of the Moon would be home of a high concentration of what we call “rare Earths“. Rare Earths are elements between atomic number 57 (lanthanum) and number 71 (lutetium) of the periodic table of elements. Rare-Earths elements’ properties are highly sought after in the automobile, aeronautics, defense and new technologies sectors. However on Earth their quantity is limited. If this lunar site is indeed home to significant deposits of these elements, this could be of great interest to these sectors.
At the same time, the Moon is said to contain a lot of helium-3, an element that makes it possible to produce clean nuclear energy, fusion. If the estimations for this element are confirmed, the quantities present on the Moon will be sufficient to meet the energy needs of humanity for several millennia.
China is the country on Earth that holds almost all of the rare Earth resources. Hence a major part of its lunar exploration program is the detection and exploitation of the resources present on the Moon. In addition Chang’e 1 and 2 were also responsible for identifying the lunar regions likely to harbour rare Earths. And Chang’e 4, which landed on the far side of the Moon, was to determine the amount of helium-3 on the Moon.
What does international law say about the exploitation of extra-terrestrial resources?
The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and other Celestial bodies of 1967 states in its article 1: “The exploration and use of outer space, including the Moon and other celestial bodies, shall be carried out for the benefit and in the interests of all countries, irrespective of their degree of economic or scientific development, and shall be the province of all mankind. Outer space, including the Moon and other celestial bodies, shall be free for exploration and use by all States without discrimination of any kind, on a basis of equality and in accordance with international law, and there shall be free access to all areas of celestial bodies“.
The article 3 also explained that any activity in the exploration and use of outer space shall be carried out in accordance with international law. This treaty formally prohibited any military use of space, the Moon and other celestial bodies. China acceded the Treaty in 1984, which has the same legal effect as ratification.
The Agreement Governing the Activities of States on the Moon and Other Celestial Bodies took up almost the same ideas as the above treaty: activities in outer space must be carried out in accordance with international law, the Moon must only be used for peaceful purposes and any military use is prohibited. However, article 7 states that the States parties to the treaty must take all necessary measures to avoid disturbing the environmental balance of the Moon.
Space law treaties were written between the 1960s and 1970s, at a time when space and lunar exploration had just begun and only scientific goals were being considered. Treaties laid down rules to preserve the celestial bodies from war and territorial appropriation. Currently there is therefore uncertainty as to the potential right to exploit lunar resources.
Hence the following question: if, for example, the rare Earth and helium-3 resources are confirmed, will it be possible to exploit them commercially?
For the moment, and due to the current economy, the exploitation of resources will not be done for Earth activities but to support the installation of humans on the Moon and why not on Mars.
The consequences of the Chang’e 5 mission
Chang’e 5 was China’s first sample-return mission and the first lunar sample-return mission to be carried out since the Soviet Union’s Luna 24 mission in 1976. Therefore China became the third country to successfully obtain samples returned from the Moon after the U.S. and Soviet Union.
The success of the mission showed that China has now mastered robotic and space techniques. In addition, China seems to be gradually opening the doors of its space program to the whole world. Whereas before it was very rare to get information, the Chang’e 5 mission was broadcast live to the whole world.
The European Space Agency also provided support the Chang’e 5 mission by providing tracking via ESA’s Kourou station, mainly during the launch and landing phases. Thanks to this collaboration with ESA, we can also notice that China seems to be more open to international collaboration, at least on certain parts of its space program.
The next step in the Chang’e program will be the launch in 2023 or 2024 of Chang’e 6, which will have the mission to land either on the far side of the Moon or at the south pole.