The Richter scale measures the energy released by an earthquake. It was developed in 1935 by California seismologist Charles F. Richter. With each increase in Richter magnitude, there is an increase of 30 times the energy released by an earthquake. For example, a 7.0 earthquake has 30 times the power of a 6.0, and an 8.0 is 900 times as powerful as a 6.0. Each earthquake only has one Richter magnitude. The strongest earthquakes are in the 8.0 range—8.6 for Alaska’s 1964 earthquake, and 8.0 for China’s 1976 earthquake in Tangshan.