According to the researchers working on the project, Beijing could employ the planetary defense system it is developing in China to protect the Earth from asteroid assaults capable of destroying entire cities (if not our civilization).
The director of China Aerospace Science and Technology Corporation, Wu Weiren , told the Xinhua news agency that the new strategy involves putting three guardian satellites with fuel and kinetic weapons into orbit around the planet to counter any threats. The plan also includes the construction of two optical telescopes on the south and north poles of the moon to monitor the sky in search of asteroids that have escaped the Earth's warning network (in particular those approaching from the blind side facing the sun).
How the Chinese asteroid defense plan works
According to the plan, when the system detects a surprise 'visitor' that has the potential to cause significant damage, it sends one or all of the guardian satellites to intercept the asteroid with an engagement time of a week - faster than it could do any large rocket launched from Earth.
“It will have the ability to intercept asteroids arriving from all directions. It can form a shield that reaches about twice the distance between the moon and the Earth about 800.000 km in diameter,” Wu and his colleagues say in an article published in the scientific journal Scientia Sinica Informationis (here an excerpt of the whole reflection).
The lunar defense line, not yet approved by the Chinese government, would take the country's space technology to new heights, the researchers say. China is building a ground defense system consisting of giant radar and telescopes in an attempt to manage an extinction event like the one that wiped out the dinosaurs some 65 million years ago.
The dangers to be evaluated
Although the possibility of an extinction-level impact remains low, approximately 60% of asteroids large enough to destroy a city have not been recorded and tracked by humans, according to an estimate by astrophysicists. None of the major Earth impact incidents from the 70s to today triggered an alarm until the asteroid hit.
“These asteroids all came from the direction of the sun,” Wu's team said. And this, perhaps, was the main problem. With the glare of the sun it was almost impossible to detect with optical telescopes: radar systems were much better at tracking known targets.
However, most of these problems could be overcome with telescopes installed directly in the polar regions of the moon. According to Wu and his colleagues, the viewing angles of lunar telescopes would almost perfectly cover the entire blind spot on Earth.
Huge costs
Obviously building similar structures on the lunar surface would cost a lot in both money and resources. The collaboration of many countries would be needed (currently the geopolitical climate is not the best). The hypothesis is that this project would involve Moscow and Beijing. A team already on the field for the International Lunar Research Station, which is expected to be completed by 2030.
It goes without saying that such a project is also designed to have implications for national security. Satellites such as those envisaged in the lunar program can monitor the geosynchronous orbit, the band where satellites from other countries are also located.
Is this one of the reasons NASA Chief Bill Nelson expressed concern about the Chinese government's lunar aims? The 'new (hopefully) cold war' moves into space, baby.
