How are the full-color images seen by the public typically created from Hubble’s raw data?

Astronomers assign visible colors (like red, green, blue) to different monochromatic observations taken through narrow filters and combine them

The stunning, full-color composite images released to the public are generally not what the cameras observe directly in a single exposure. Raw data collected by instruments like WFC3 or ACS primarily consists of measurements of light intensity across very narrow color bands, often resulting in monochromatic (single-color) images. To create a rich, visually informative composite, astronomers map specific visible colors—such as red, green, or blue—to the intensity data gathered through different filters. For instance, one filter might capture blue light, another red light, and a third might capture light slightly into the infrared range. Combining these layered images allows scientists to map specific chemical signatures or temperature distributions that would be indistinct or dim in a simple unfiltered view.