Huh?? did any one else hear about this back then? Thats pretty scary. you know it is near impossible to detect an asteroid this small on its way to hit us- something coming right at you will not move left or right very much, and will seem like a fixed point of light or worse- it is coming at us from the direction of the sun and will be black in shadow
Several paragraphs into the article they explained that it didn't really explode with the force of an atom bomb all at once, but it was fun to say that it did in the opening paragraphs and would probably also drew more readers in and sold more newspapers.
In general, when fast moving things the size of a house slow to a stop in a very short period of time, a lot of energy is expended. It's sort of like making the statement that 'the collective energy of the ocean tide hitting the Atlantic coast is like an atomic bomb going off every 6 hours'. The amount of energy released is equivalent, but the effect of concentrating all that energy in one tiny place at one time makes all the difference.