知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。 ↑ The animation depicts a mapping on the positions of regarded in the vicinity of-Earth objects (NEOs) at details in time over the past 20 years, and finishes by using a map of all identified asteroids as of January 2018. Asteroid look for groups supported by https://uyure.net/animaciebi-qartulad/