When we get to units of time larger than weeks, however, we encounter problems because not all months have the same number of days, a year is not exactly \(52\) weeks, and the time it takes for the Ea...When we get to units of time larger than weeks, however, we encounter problems because not all months have the same number of days, a year is not exactly \(52\) weeks, and the time it takes for the Earth to orbit the Sun is not exactly \(365\) days. The destructive power of nuclear weapons is measured in kilotons (the equivalent of \(1,000\) tons of TNT) or megatons (the equivalent of \(1,000,000\) tons of TNT).