Some scientists believe that the collision of one or more large asteroids with the Earth was responsible for the extinction of the dinosaurs. The unit of kiloton is used to describe the energy released during large explosions. It was originally defined as the explosive capability of 1000 tons of trinitrotoluene (TNT) high explosive. Because that expression can be imprecise depending on the explosive's exact chemical composition, the kiloton subsequently has been redefi ned as the equivalent of 4.186 3 1012 J. In the units of kiloton, calculate the kinetic energy of an asteroid that has the size (box-shaped, 13 3 13 3 33 km) and composition (density, 2.4 g/cm3) of our solar system's asteroid Eros. Kinetic energy is defi ned by Uk = 1/ 2mv^2 where m is the object's mass and v is its speed. Objects passing through the inner solar system generally have speeds in the range of 20 km/s.