China Sends Life to Moon


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Later this year, China will launch a spacecraft to the Moon and back. A scale replica of the Shenzhou astronaut capsule will be carried atop a boxy spacecraft based on the Chang’e lunar orbiter, and launched by a Long March 3C rocket.
The mission was originally expected to simply fly around the Moon on a “free-return” trajectory, but recent reports in China’s state-run media claim that the spacecraft will actually enter orbit around the Moon. Then the spacecraft will fly back to Earth, and the Shenzhou replica capsule will make a soft landing in China.
The mission seems to have two purposes. China claims that the flight is a test of the capsule to be used on a future robotic sample-return mission to the Moon. This is widely understood and believed. A more controversial idea, not officially stated by China, is that the mission is linked to future plans for launching Chinese astronauts to the Moon. Why else is a replica of their own astronaut capsule being used for the flight?
The mission is thus mostly about performing engineering tests. Returning from the Moon is more difficult than returning from Earth orbit. Apart from the need for precise navigation, the re-entry is much faster, and places more demands on a spacecraft’s heatshield. China has mastered re-entry from orbit for decades, but has yet to recover anything from deep space.
While there’s a lot of interest in the simple act of flying to the Moon and back, other questions are being raised about what will lurk inside the capsule. So far, China has offered few clues.
This analyst previously estimated that the re-entry capsule is around 1.5 metres across at its base. It isn’t clear how much internal volume the capsule has, but it obviously can’t accommodate a lot of gear. Nevertheless, there’s enough room for some productive experiments.
This analyst expects that much of what lies inside will be focused on the effects of radiation in deep space. This could be a hazard to equipment and personnel on future missions. Thus, we can expect that radiation detectors will be placed inside the capsule.
This will explore the higher radiation levels found at lunar distances and also allow the radiation shielding properties of the capsule to be tested. Some detectors could be located outside on the main spacecraft “bus” to provide a comparison.
There will also be biological samples. China has been launching plant seeds into space for a long time. They are easy to store, take up little space, and can be studied simply by seeing how they germinate after their return. We can safely bet that seeds will be carried on this mission.
There could also be micro-organisms stored in small vials. Cell tissue from more complex animals could also be carried. Perhaps there will even be small insects such as fruit flies. But we can rule out any complex animal life, which requires large and complex life-support systems. The goal will be to fly items that are small and easy to store.
The recent problems experienced by the ill-fated Russian Foton M4 recoverable capsule illustrate how a complex biological package can go wrong. The fruit flies on this mission survived. The geckos did not.
We can probably rule out any centrifuges being included. They are fairly bulky and complex. There are already enough new complexities on this mission, and biological science is really a secondary goal.
China will also probably fly small flags for mainland China, Hong Kong and Macau. These will eventually turn up in museum exhibits.
This mission could easily blast off within a matter of weeks. China has stated that the mission will fly before the end of the year. They will not want to wait for winter to strike with full force, which could complicate the launch and the recovery of the spacecraft. So a launch before mid-November seems certain.
The countdown is on, but China still hasn’t said a lot about the mission. This analyst expected more details to emerge by now. Perhaps the slightly covert agendas of this flight, which supports plans for human lunar flight, is producing a tighter veil of secrecy.

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