75th 6.0 Magnitude Aftershock In Japan

Famous Earthquakes are usually arranged by their magnitude on the Richter scale. In comparison, a tornado can rumble with Richter scale magnitude of 4.8, and a 1-megaton nuclear bomb can measure 7.5 on the Richter scale. The highest magnitude earthquake recorded to date - at about 9.6 - was the 1960 Chilean earthquake, in which a fault 621 miles(1,000 kilometers) long slipped 33 feet (10 meters). source

Live Science: 75th Aftershock of Magnitude 6 or Higher Hits Near Japan