Figure 3: The left image shows real data, while the right image shows the equivalent simulated tile. Note that large foreground objects like stars our own galaxy are not simulated. In fact, these bright objects get masked out of our data analysis since they don’t tell us much about structure and are incredibly bright. Since we apply the same masks to the right hand tile, there’s no need to simulate them. (Credit: DES Collaboration, MacCrann, et al., 2021.)