Sunspot number

Alternative definitions (1), class: vernacular (0)
Term: Sunspot number

A quantity which gives the number of sunspots at a given time. It is defined by the relationship R = k(10g + f), where R is the sunspot number, k is a constant depending on the observation conditions and the instrument used, g is the number of the groups and f is the number of individual spots that can be counted.

Created 2023.04.16
Last Modified 2023.04.16
Contributed by Ryan McGranaghan