Moment magnitude scale both scales. Unlike other scales, the moment magnitude scale does not saturate at the upper end; there is no upper limit to the possible measurable magnitudes. However, this has the side-effect that the scales diverge for smaller earthquakes. Various ways of determining moment magnitude have been developed, and several subtypes of the scale can be used to indicate the basis used. Moment magnitude scale The moment magnitude scale (MMS; denoted as M" or M") is one of many seismic magnitude scales used to measure the size of earthquakes. The scale was developed in the 1970s to succeed the 1930s-era Richter
Absolute magnitude and a difference of n magnitudes in absolute magnitude corresponds to a luminosity ratio of 100. For example, a star of absolute magnitude M=3 would be 100 times more luminous than a star of absolute magnitude M=8 as measured in the V filter band. The Sun has absolute magnitude M=+4.83. Highly luminous objects can have negative absolute magnitudes: for example, the Milky Way galaxy has an absolute B magnitude of about −20.8. An object's absolute bolometric magnitude represents its total luminosity over all wavelengths, rather than in a single filter band, as expressed on a logarithmic magnitude scale. To convert