The Near-Earth Object Observation Program, commonly called "Spaceguard, " also plots the orbits of these objects to determine if any could be potentially hazardous to our planet.

近地天体观察项目，常被叫做“太空警卫”，也对这些天体绘制了轨道图来判断其中是否有天体可能对我们的星球有潜在危险。

youdao

Mainzer said between 20% and 30% of the estimated 4, 700 potentially hazardous objects have been discovered so far.

CNN: NASA estimates 4,700 'potentially hazardous' asteroids

More than 1, 300 near-Earth objects have been classified as potentially hazardous to Earth, meaning that someday they may come close or hit our home planet.

CNN: While you were working: An asteroid just flew by