Overview of the eROSITA η Cha field scan observation. X-ray exposure map (top) with linear scaling to facilitate showing the scanning direction and spacecraft maneuver holding points. The color scale denotes exposure in (s). A comparison of the X-ray and optical images of the cluster core showing the same sky region (middle), and an X-ray image of the η Cha field (bottom) in which known (red) and new (yellow) cluster members are marked. The field contains nearly 8000 X-ray sources.