China has commissioned a group of scientists to study the feasibility of building a manned radar station on the moon, but many experts on the mainland have questioned the potentially massive cost of the project and the usefulness of building such a base.
The government project was launched earlier this year and received kick-start funding of 16 million yuan (HK$18.7 million) from the National Natural Science Foundation of China, according to its website.
The proposed facility, which may include quarters for astronauts and a powerful radar antenna array at least 50 metres high, could monitor wider areas of our planet than existing satellites, according to scientists involved in the study.
The base, which would be used for scientific research and defence monitoring, could also produce more powerful and clearer images of earth as the high-frequency microwaves emitted by the radar station could not only penetrate cloud, but also the earth’s surface, allowing it to monitor areas on land, under the sea and underground.
Leading space scientists in China have joined the radar station project.
The team held a two-day brainstorming session at the Fragrant Hill Hotel in Beijing last month.
Those taking part included Yan Jun, the director of the National Astronomical Observatories; Professor Lin Yangting, a planetary researcher whose team discovered evidence of coal-like carbon in an asteroid; and senior scientists from China’s unmanned lunar exploration missions.
The team leader is Professor Guo Huadong, a top radar technology expert at the Chinese Academy of Sciences.
Guo initially proposed the moon-based radar station in a research paper in the journal Science China Earth Sciences three years ago.
He suggested the moon had numerous advantages over satellites or a space station as an earth observation platform, including stability and the unlimited durability of any complex on the lunar surface.
The data collected by lunar radar would help with a wide range of scientific research issues such as monitoring extreme weather conditions, global earthquake activity, agricultural production and the collapse of the polar ice caps, he wrote.
To generate high intensity radio beams that could reach earth, the radar station would need an enormous amount of power so a solar or nuclear power plant would have to be built, Guo said in the paper.
The radar would generate at least 1.4 gigabytes of data each second, a volume far exceeding the bandwidth of current long-distance space communications technology, but this would not be a problem if the station was manned by astronauts who could process the information on site, he added.
Guo gave no precise estimate on costs for the project, but cautioned it would be “very expensive”. He did not respond to requests for comment.
Many researchers interviewed by the South China Morning Post, however, expressed scepticism about the scheme, arguing it was a waste of money, time and human resources.
“It’s a lunatic idea,” said one mainland space scientist informed of the project, but not directly involved.
The cost of building such as a large scale facility on the moon would be “higher than filling the sky with a constellation of spy satellites”, which could “do the same job at only a fraction of the cost”, said the scientist, who declined to be named due to the sensitivity of the issue.
Professor Zhou Yiguo, a radar technology researcher at the Chinese Academy of Sciences’ Institute of Electronics, said the distance between the moon and earth, 10 times further than the highest orbiting satellites, would cause enormous technological challenges.
“Either the radar has to be extremely powerful, or the antenna extremely large, otherwise it won’t be able to pick up the radio waves bouncing back from the earth,” he said.
“It is an important subject of research, but whether its advantage over satellite constellations can adjust the high cost and risk will need careful evaluation,” he added.
The lunar radar project comes as China shows signs of wanting to play a leading role in a renewed race to the moon, according to some space experts.
The design of a giant rocket the same size as the Saturn V in the US Apollo missions will be completed by 2020 to pave way for large scale activities in space including a “manned moon landing”, according to a scientific and technological innovation plan announced by the central government earlier this month.
China’s scientific authorities appear optimistic about the prospects for the lunar radar base, despite the concerns voiced by some experts.
Chai Yucheng, executive deputy president of the national science foundation, said at a meeting with the project team in April that the moon-based observational facility played a key role in China’s future scientific blueprint.
The government expects a “significant breakthrough” in the scheme by 2020 when the deadline comes for the team to submit its final report, Chai was quoted as saying on the Chinese Academy of Sciences website.