(a) Position of 8678 campfires (color dots: the total intensity of campfires) and supergranular boundaries (white lines). The color map indicates the pixels’ integrated intensity of campfires. (b) Average of 50 HRI_Lya images, supergranular boundaries (white lines), and position of campfires (green dots). (c) Frequency (number) of campfires’ shortest distances (distance (D) of campfires centroid from the supergranular boundaries) for HRI_Lya intensity < 400 DN/s (blue line), 400–900 DN/s (black line), and > 900 DN/s (red line). About 2/3 of campfires have the HRI_Lya intensity of the centroid in the range of 400–900 DN/s.