When an asteroid hits Earth - level 2
An organisation released a video. It shows an asteroid which hits Earth. The group uses the video to say that impacts of asteroids are common, more common than scientists believed.
The video uses data from a global network. The network listens to nuclear weapons detonations. Between 2000 and 2013, 26 big explosions were detected. They were not caused by nuclear weapons but by asteroids.
NASA watches asteroids which are larger than 1 kilometre.
Difficult words: impact (the moment when one thing hits another), detonation (explosion), detect (to notice or discover).