China targets its first planetary defense test mission

The new JDSE article also helpfully lays out hitherto undisclosed science goals and payloads, revealing what China hopes to learn from the mission. 

The main aims are, of course, conducting impact experiments and observing the entire impact process. Beyond this though, the mission aims to study the dynamic evolution, origin, and orbital migration history of the target asteroid, including any close encounters with planets. This could provide valuable data on asteroid populations, to which only a handful of missions have flown.

Key objectives for studying the asteroid are determining its size, shape, composition, internal structure, thermal radiation, and the presence of volatiles. Furthermore, estimating the asteroid’s mass, density, and porosity could bring insights into its formation and evolution. By extension, this could provide clues for understanding the origin and evolution of the Solar System.

Meanwhile,  a comprehensive observation of 2015 XF261 will be conducted to determine the asteroid’s orbital parameters, rotation, and reflectance characteristics. This data will help build precise asteroid evolution models and evaluate impact effects on near-Earth asteroids.

Payloads

Payloads will include spectral and Laser 3D detectors, color cameras, radars and dust and particle analyzers.

The spectrometer and laser payloads will be used to determine the asteroid’s composition and classification. High-resolution color cameras will be used to observe and model the asteroid’s surface features and to assist in impact point selection. A radar payload will be used to peek inside the asteroid and build internal structural models, created from reflected signals echoing back from the asteroid. Finally, particle analyzers will focus on the composition and environmental effects of dust and particles.

Together with the lessons from DART and Hera, China’s mission would significantly advance humanity's capabilities in planetary defense and our understanding of asteroids themselves, providing multiple new data points as we seek to safeguard Earth from potential asteroid impacts.

It would further verify kinetic impact techniques, with post-impact assessments providing greater insight into the effects of impact deflection.

Spotting new NEOs

Meanwhile, China is also stepping up its observation of near-Earth objects, not just nudging their orbits. The 2.5-meter Wide Field Survey Telescope (WFST) in Lenghu, Qinghai Province, saw first light in autumn 2023 and had spotted two new asteroids by November. Also up and running are the Lijiang 2.4-meter and the Xinglong 2.16-meter telescopes. Other survey telescopes for monitoring have also been proposed.