Apparent Area as a Basis for Solar Flare Importance

If flare importance, based primarily on area, is to be insensitive to the flare's position on the solar disk, we need to know how apparent area depends on position. Earlier studies show that the ratio of corrected to apparent area seems to differ between small and large flares. Calculations based on a simplified model show that this apparent dependence is not real, but is introduced by observational loss of small flares. A relation between corrected area and apparent area that depends on central distance alone provides an adequate description of extensive world-wide flare data.