欧洲欲建太空"防护盾" 防范小行星撞地球

Nevertheless, with NASA estimating that there are almost one thousand asteroids over one kilometre in length and 19,500 over 100-metres, scientists at the Institute of Planetary Research are trying to find a way to protect Earth.

然而，美国宇航局估计现在银河系约有1000颗长度超过1千米的小行星和19500颗长度超过100米的小行星，因此行星研究所的科学家们正努力探寻保护地球的办法。

With an investment of some