Only an amateur observer and occasional paper browser, but my general take is that there are an awful lot of prior models of everything from the stellar nucleop

Only an amateur observer and occasional paper browser, but my general take is that there are an awful lot of prior models of everything from the stellar nucleophysics up through environmental effects in nurseries, nebulae, galaxies, clusters, etc. Years and years of observations, hypothesizing, and refining with even more observations combine to give a halfway decent storyline of many processes at all scales. These are then fit against new observations and either refined or modified or expanded to give new data a home as well. All in all, a very cool example of the scientific process working itself out just as it should and can.