Lead

China is moving forward on two fronts to protect Earth from asteroid impacts: building an early warning system and planning a high-speed spacecraft collision mission, according to the scientist leading the national effort and a newly released research paper.

Li Mingtao, chief scientist at the asteroid monitoring and early-warning research centre under the China National Space Administration, said China plans to deploy multiple telescopes on the ground and a constellation of satellites in orbit to spot potentially dangerous near-Earth objects. His remarks were carried by state-run Science and Technology Daily on June 30, a date the United Nations has designated as International Asteroid Day.

Separately, a paper outlining China's first planetary defence mission describes plans to slam a spacecraft into an asteroid before 2030, with an impact speed of more than 9 km (5.6 miles) per second — over 26 times the speed of sound near sea level.

Coverage Comparison

Reports from the South China Morning Post covered both the early warning system and the planned impact mission. The first report focused on Li's statements about the warning system, describing the risk posed by undiscovered asteroids. The second report compared China's mission with Nasa's Double Asteroid Redirection Test (Dart), which in 2022 successfully nudged an asteroid's orbit around another body.

Both articles drew on Li's expertise and the research paper, with the second noting that the paper is under peer review by the Chinese-language Journal of Deep Space Exploration.

Key Claims

  • China is developing an early warning system using ground-based telescopes and a satellite constellation, as reported by the South China Morning Post citing Li Mingtao.
  • More than 95% of near-Earth asteroids larger than 1 km in diameter have been identified, according to Li. Such objects could trigger global catastrophes.
  • Only about 45% of asteroids measuring around 140 metres across — enough to devastate a small country — are believed to have been discovered, Li said.
  • Li described undiscovered near-Earth asteroids as the greatest risk, noting they are numerous, very faint before their approach, and may suddenly come from the direction of the sun.
  • China's planetary defence mission plans to slam a spacecraft into an asteroid before 2030, with the aim of directly altering its orbit relative to Earth or even breaking up its structure, according to the research paper.
  • The spacecraft is expected to hit its target at more than 9 km per second during a close approach to within about 7 million km of Earth in 2029 or 2030. This is faster than Dart's impact speed of 6.1 km/s.
The South China Morning Post noted that no discovered asteroids are thought to be on a clear collision course with Earth, based on Li's remarks.

Perspectives

Li Mingtao, chief scientist at the China National Space Administration's asteroid monitoring and early-warning research centre, provided the assessments on asteroid discovery rates and the warning system's design. His comments underscore the official Chinese view that undiscovered asteroids pose the greatest threat.

The research paper's authors, led by Li, present the mission as a more ambitious test than Nasa's Dart, aiming for a direct alteration of an asteroid's orbit or structural breakup. The paper's claims about impact speed and timing are attributed to the team's calculations.

No other official perspectives were included in the reports reviewed.