Analyzing an image taken with an X-ray telescope

bkg_noise

A very important process in observational astronomy is to carefully subtract the background noise from an image taken by an X-ray telescope. This background noise may come from background photons, i.e., photons not associated with the source that is being observed or artefacts from the telescope itself. For that purpose, scientists develop software tools that are used to analyse observations taken by X-ray telescopes.