Richter magnitude scale against the distance, and found a series of curves that showed a rough correlation with the estimated magnitudes of the earthquakes. Richter resolved some difficulties with this method, then, using data collected by his colleague Beno Gutenberg, produced similar curves, confirming that they could be used to compare the relative magnitudes of different earthquakes. To produce a practical method of assigning an absolute measure of magnitude required additional developments. First, to span the wide range of possible values Richter adopted Gutenberg's suggestion of a logarithmic scale, where each step represents a tenfold increase of magnitude, similar to the magnitude scale
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