China has changed the launch date and purpose of a mission that will attempt to demonstrate its ability to divert the orbit of an asteroid. Speaking at the 45th Scientific Meeting of the Committee on Outer Space Research (COSPAR) on July 15, Li Mingtao of the National Center for Space Science of the Chinese Academy of Sciences said 2027 is the new launch date for the mission. The spacecraft will collide with a small asteroid and observe further collisions.

That date was two years after another Chinese official announced at a conference in April 2023 that the mission was scheduled to launch in 2025. Lee did not explain the reason for the delay. The mission also has a new target. Lee said the mission’s target will be the asteroid 2015 XF261, which has a body about 30 meters in diameter. It is about the same size as the mission’s previous target, 2019 VL5.

He said the two spacecraft will be launched together on Long March 3B in 2027. The observation spacecraft will fly by Venus before arriving near the asteroid in early 2029. About three months later, in April 2029, the impactor will collide with an asteroid at a speed of 10 kilometers per second. This will happen when the asteroid comes within seven million kilometers of Earth.

This schedule means that the asteroid impact will occur within the same month that another near-Earth asteroid, Apophis, will pass very close to Earth. Several space agencies are considering missions to study Apophis before or after the flyby. Lee did not mention any plans for that, but did say that 2029 will be the year of “asteroid awareness and planetary protection.”

The mission’s goal is to demonstrate a “kinetic impactor” approach to planetary protection, and to show how a high-speed collision could alter an asteroid’s orbit to prevent a potential collision with Earth. NASA demonstrated the same concept with its Double Asteroid Redirection Test (DART) mission in 2022, which collided with the lunar-orbiting asteroid Didymos, changing its orbital period by more than half an hour.

One difference is that 2015 XF261 is significantly smaller than Didymos and its companion Dimorphos, allowing astronomers to directly measure the change in its orbit. A collision could destroy the asteroid entirely rather than deflect it, one scientist at the COSPAR session noted.

“It could really destroy a small asteroid,” Lee admitted, adding that scientists had modeled the impact. “Even if we were to destroy it, it would also provide a method, a way to deflect a small asteroid. That would make it possible to study the internal structure of a small asteroid.”

The mission does not yet have a name, but he said China was considering a global competition to choose a name and logo for the mission, as part of an initiative that could include research into the design of future planetary defense missions.

Lee said his center is considering several additional concepts for deflecting or destroying an asteroid, including one that would use the upper stage of a launch vehicle as an impactor to increase the energy delivered. Another concept, inspired by NASA’s canceled Asteroid Redirect Mission, is to try to capture an asteroid. He said there is no deadline for those missions.

China is also exploring concepts for a space observatory to search for near-Earth asteroids, similar to NASA’s Near-Earth Object Explorer mission, which is being developed for launch in 2027. Lee said the concepts explore several “new orbits,” including the Sun-Earth L-1 Lagrange point, locations ahead or behind Earth in its orbit around the Sun, and even a constellation of spacecraft in a retrograde orbit around the Moon. He said there is no timetable yet for the development of the observatory.