Asteroids can sometimes be viewed as “fossils” of the solar system, containing metals like iron, nickel, and platinum that hold clues to planetary formation. At the same time, near-Earth asteroids (NEAs) also pose one of humanity’s greatest existential threats. Even an object a few hundred meters wide could cause widespread damage if it collided with Earth. The geological record indicates that such impacts have occurred in the past and will likely happen again.
According to China’s space agency, the government is preparing to test a direct method of planetary defense by sending a spacecraft to collide with an asteroid and change its trajectory. Wu Weiren, chief designer of China’s lunar exploration program, announced that a kinetic impact demonstration mission is planned for later this year, though an exact launch date has not been made public. If the mission succeeds, China will be the second country, after the United States, to alter the orbit of a celestial object.
The Mission Plan
Wu explained that the test will focus on a small asteroid located tens of millions of kilometers from Earth. The mission will use two spacecraft: one to observe and collect data, and another to impact the asteroid at high speed. The event will be monitored using telescopes on the ground and in space.
The mission aims to change the asteroid’s orbit by only 3 to 5 centimeters. Although this adjustment is small, it demonstrates the principle of planetary defense. If such changes are made early, even minor shifts can prevent a collision many years in the future.
Wu outlined plans for a comprehensive Chinese asteroid defense system that would encompass early warning, in-orbit response, and coordinated preparedness. He stated that kinetic impact would be the primary approach, but future systems might utilize additional technologies. Wu also expressed interest in sharing data and working with other countries to build a joint asteroid defense capability.
Following in DART’s Footsteps
China’s plan comes nearly three years after NASA’s Double Asteroid Redirection Test (DART) mission, which deliberately crashed a spacecraft into the asteroid Dimorphos in September 2022. That mission shortened Dimorphos’ orbit around its parent body, Didymos, by 33 minutes—far beyond scientists’ expectations.
DART was the first mission to demonstrate that asteroid deflection is possible, transforming planetary defense from a theoretical concept into a practical technique. If China completes its test, it will provide a second example, this time from a country that is quickly advancing its deep-space exploration program.
China’s space program has made rapid progress in recent years. The Tianwen-2 probe, launched in May, will collect samples from the asteroid 2016 HO3 and later investigate a main-belt comet. China’s lunar missions have already deployed landers, rovers, and orbiters. The planned asteroid deflection test is a new step, moving from exploration toward planetary defense.
Importance of Planetary Defense
Advances in detection technology have allowed scientists to find more near-Earth objects. By 2021, over 26,000 NEAs had been cataloged, with more than 2,100 considered potentially hazardous by NASA. Most do not pose an immediate threat, but even a small number can present significant risks.
Earth’s geological record documents the consequences of asteroid impacts. The extinction of the dinosaurs 66 million years ago was caused by a 10-kilometer-wide impactor. In 2013, a 20-meter asteroid exploded over Chelyabinsk, Russia, injuring over 1,000 people. This event illustrates that even small asteroids can cause major damage to populated areas.
Planetary defense experts emphasize the need for global preparation. In 2023, the United States released a national planetary defense strategy that outlines a ten-year plan to enhance detection, modeling, and response to asteroid threats. Since asteroid impacts can affect the entire planet, international cooperation is essential for the future of planetary defense. China’s announcement highlights the mix of rivalry and partnership in planetary defense. It reflects technological competition with the United States, but also shows, as Wu notes, that protecting Earth from asteroids is a task best met with global teamwork.
It’s unclear if the mission will launch this year, as officials haven’t set a final date. Still, U.S. and Chinese asteroid deflection efforts mark key progress. Planetary defense is becoming a practical field of space science and engineering.
Future Prevention
If China’s mission succeeds, it will offer a second practical demonstration of asteroid deflection. The data collected will help refine our understanding of how asteroids react to kinetic impacts and provide information to guide future strategies for deflecting larger and more potentially hazardous objects.
Asteroids provide unique insights into both the solar system’s vast history and its persistent risks. Each successful demonstration of deflection technology advances our ability to anticipate and potentially prevent future impacts.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds a Master of Business Administration and a Bachelor of Science in Business Administration, along with a certification in Data Analytics. His work combines analytical training with a focus on emerging science, aerospace, and astronomical research.