A visual method of estimating the magnitude of a variable star, described by F. W. A. Argelander. It involves comparing the variable with a comparison star, assigning a step value that reflects the ease with which the brightness of the variable can be distinguished from that of the comparison. Estimates of the form ‘A(3)V, V(1)B’ result, and the magnitude of the variable (V) can be calculated from the known magnitudes of the comparisons (A and B), as with the fractional method. See also Pogson Step Method.
Subjects: Astronomy and Astrophysics.