“The first this to understand about the KT event is that is was absolutely enormous: an asteroid (or comet) six to 10 miles in diameter streaked through the Earth’s atmosphere at 25,000 miles an hour and struck the Yucatan region of Mexico with the force of 100 megatons -the equivalent of one Hiroshima bomb for every person alive on Earth today. Not a pretty scenario! “
Let’s see ... 100 megatons = 100 x 10^6 / 12.5 x 10^3 (Hiroshima bomb yield) = 10,000.
Correct me if I’m wrong here, but 10,000 does not quite equal 6,000,000,000.
Maybe they meant gazilliatons?
20 kilotons = 2 x 104 tons