Published online by Cambridge University Press: 19 July 2016
The topic (Seidelmann, 1986) is one of the unresolved questions in the field of celestial mechanics because the definitions of an inertial system are all controversial (Mach, 1893; Eichhorn, 1984). Eichhorn's definition enlarges its connotation and is not acceptable either. Connotation of a concept is endowed through defining it. One of the reasons why the existing definitions of an inertial system are all controversial is that the connotations that are endowed by them are not unique, in other words, they do not draw up the same area of ideas. Taking the interplay of all of them for its connotation is an acceptable solution.