Following NASA, the Chinese space agency is also investigating whether an asteroid could be deflected by a kinetic impact.
The recently published science program plan calls for a mission to launch before 2030, with a target asteroid 30 meters in diameter. Asteroid 2019 VL5, then 2015 XF261, has been suggested as a possible target—the actual target will likely be determined when the program reaches its actual launch window.
Determining the window is no simple puzzle, as two mission-carrying devices are launched on a launch vehicle, but one of them arrives at the same destination months later. One is a compact, high-energy impactor, and the other is a monitoring unit equipped with several devices.
Before the impact broadcast, the observatory will spend a year collecting data on the asteroid. It will also carry a high-resolution color camera, a 3D laser detector, a radar and a dust analyzer, with which they hope to get a glimpse of the asteroid's interior during the impact.
China has been flirting with the idea of adding a planetary defense thrust to its space program for some time. The first plans published in 2023 targeted the 2019 VL5 rocket, with the kinetic rocket scheduled to launch in 2025.
Physicist Wu Weiren, the chief engineer of China's lunar program who was recently appointed director of the Deep Space Research Laboratory in April, also provided more specific details: The mission will launch in 2027 on a Long March-3B rocket.
We are superior to primitive lizards.
NASA first attempted to crash into Comet Tempel-1, but the real diversion was 2022 DART. This mission targeted the planet Dimorphos, which orbits Didymos, and, to the delight of experts, managed to change its orbital period. The 177-meter-tall Dimorphos rocket, much larger than the Chinese target, partially disintegrated upon impact with its 610-kilogram thruster, then partially reassembled itself under its own weak gravity. Half of the 37 large rocks that broke off are slowly returning, while the other half escaped and will crash into Mars in the next few thousand years.
Scenarios presented at NASA's biennial international planetary defense conferences regularly reveal that we are hopelessly unprepared to fend off an Earth-threatening asteroid. Earlier, it turned out that half a year is not enough for protection. More recently, a more friendly 14-year period was taken as a basis, but this seems to have been too long – and here political and economic cycles have already affected the time-wasting effect of bureaucracy.
In light of this, it is of course encouraging that China is also interested in protecting the planet, as it means more expertise, technical knowledge and opportunities.
Planning isn't everything, last month Chinese experts
A drill that took place in early 2022 was declassified,
Special measurements were made using the Jilin-1 satellites, the country's largest commercial satellite system. The devices were built to take high-resolution images and videos of the Earth's surface (such as the movements of U.S. F-22 stealth fighter jets), but it has been suggested that they may also be suitable for monitoring threatening asteroids. The experiment showed that Jilin-1 was able to track and monitor the 1-kilometer-wide object 1994 PC1, considered a dangerous near-Earth object, far beyond the orbit of the moon, from a distance of 2 million kilometers.
Western countries were surprised by China’s technical capabilities. On the other hand, it may come as a surprise to Eastern partners that Chinese and Ukrainian astronomers have jointly developed a method for effective detection of hazardous asteroids. In images taken between 2011 and 2023 by the 50-centimeter telescopes of the Mykolaiv Astronomical Observatory and the Shanghai Astronomical Observatory, fast-moving objects appear as elongated lines, but the new so-called RDS survey procedure was able to interpret them as points. The accuracy of the measurements was improved. This is a major advance for surface systems used to monitor nearby asteroids. Regarding the result, Chinese Vice Premier Ding Hsu-hsiang stressed the importance of respecting science and upholding the national, sincere and innovative scientific spirit.
According to plans, NASA will launch the NEO Surveyor satellite in the summer of 2028, which will be used specifically to monitor objects passing near Earth. Overall, our chances are slowly but surely improving.
(Global Village Area, Interesting engineering, Planetary Society)