The objective of this study is to understand the scientific inferential processes of Galileo's discovery of Jupiter's moons. Abductive reasoning has played very important roles in producing creative leaps and breakthrough for scientific discovery in history of science. This article presents a scientific procedure that involves abductive inference in general. And we propose a noble and refined model for abduction inference and show its validity by applying to the inferential process of "Galileo's discovery of the moons of Jupiter", with historically considered evidence. It makes three broad macro perspectives; rather than only hypothetico-deductive method, (1) "fixed stars hypothesis suspected", (2) Moon hypothesis can be suggested and selected by abductive strategies, (3) Moon hypothesis expansion.