BUSAN, South Korea – China has changed the launch date and target for a mission that will try to demonstrate the ability to deflect an asteroid’s orbit.
Statement before the Committee on Space Research (COSPAR) 45th Science Assembly here on July 15 Li Mingtao of the National Space Science Center of the Chinese Academy of Sciences said 2027 is the new launch date for the mission, which will send one spacecraft to collide with a small asteroid and another to observe the impact .
The date is two years later than what another Chinese official announced at a conference in April 2023, saying the mission was scheduled to launch in 2025. Li did not reveal the reason for the delay.
The mission also has a new destination. Li said the mission’s target will be asteroid 2015 XF261, a body estimated to be about 30 meters in diameter. This is roughly the same size as the mission’s earlier target, 2019 VL5.
He said the two spacecraft will launch together on Long March 3B in 2027. The observer 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 the asteroid at a speed of 10 kilometers per second. This will happen when the asteroid is seven million kilometers from Earth.
This schedule would mean that the asteroid impact would occur the same month that another near-Earth asteroid, Apophis, flies very close to Earth. Several space agencies are considering missions to explore Apophis before or after the flyby. Li did not mention any plans for this, but noted that 2029 will be a year of “knowing about asteroids and protecting the planet.”
The purpose of the mission is to demonstrate the “kinetic impact” approach to planetary defense by showing how a high-velocity impact can alter an asteroid’s orbit to prevent a potential collision with Earth. NASA demonstrated the same concept with its Dual Asteroid Redirect Test (DART) mission, which collided with a moon orbiting the asteroid Didymos in 2022, changing its orbital period by more than half an hour.
One difference is that 2015 XF261 is significantly smaller than both Didymos and its companion Dimorphos, allowing astronomers to directly measure the change in its orbit. One scientist at the COSPAR session noted the possibility that the impact would completely destroy the asteroid rather than deflect it.
“It does have the potential to destroy the small asteroid,” Li admitted, saying scientists had made models of the impact. “Even if we break it, it will also provide a method, a way to deflect a small sized asteroid. This will make it possible to study the internal structure of a small asteroid.
The mission doesn’t have a name yet. However, he said China is considering a global competition to choose a name and logo for the mission, part of an initiative that could also include design studies for future planetary defense missions.
Li said his center is looking at several additional concepts for deflecting or breaking up an asteroid, including one that would use the launch vehicle’s upper stage as an impactor to increase the energy delivered. Another concept, inspired by NASA’s canceled Asteroid Redirect Mission, would aim to try to capture an asteroid. There is no timetable for these missions, he said.
China is also studying concepts for a space observatory to search for near-Earth asteroids, similar to NASA’s Near Earth Object Surveyor mission, which is being developed for launch in 2027. Li said the concepts explore several “new orbits” that include the sun- Earth’s L -1 Lagrange point, places that lead or follow Earth in its orbit around the sun, and even a constellation of spacecraft in distant retrograde orbit around the moon. There is no timetable yet for the development of this observatory, he said.
