1999 Jiji earthquake The tremor measured 7.6 on the Moment magnitude scale, 7.3 on the Richter scale, and the focal depth was . The Central Weather Bureau recorded a total of 12,911 aftershocks in the month following the main tremor. The total energy released is estimated to be 2.1 × 10 J, approximately the same as the yield of the Tsar Bomba. The earthquake was in an unusual location for Taiwan, which experiences the majority of its earthquakes off the eastern coast, such quakes normally causing little damage. One of the aftershocks, on 26 September, was a strong earthquake in its own right,
Order of magnitude An order-of-magnitude difference between two values is a factor of 10. For example, the mass of the planet Saturn is 95 times that of Earth, so Saturn is "two orders of magnitude" more massive than Earth. Order-of-magnitude differences are called decades when measured on a logarithmic scale. Other orders of magnitude may be calculated using bases other than 10. The ancient Greeks ranked the nighttime brightness of celestial bodies by 6 levels in which each level was the fifth root of one hundred (about 2.512) as bright as the nearest weaker level of brightness, and thus the brightest level being