在这部防御小行星任务纪录片片中,讲述我们人类生活的地球，面临着宇宙中小行星的威胁，美国宇航局探索、研究并防御小行星任务的一部纪录片。
Assuming a big asteroid is on it's way to hit the earth. Are we able to stop it in any way, or are we destined to have the same faith as the dinosaurs? NASA is looking for hazardous asteroids threats, where some are the size of the fireball who exploded over Chelyabinsk, Russia in 2013. And some are big enough to wipe out all human civilization.
