Twenty-four free-response questions were developed to explore introductory college astronomy students' understanding of gravity in a variety of contexts, including in and around Earth, throughout the solar system, and in hypothetical situations. Questions were separated into three questionnaires, each of which was given to a section of introductory college astronomy with 143, 137, and 32 respondents, respectively. Combined with 15 interviews, the exploratory, open-response format allowed themes to emerge naturally, with both documented and undocumented misconceptions observed. The breadth of questions allowed for descriptions of possible student mental frameworks, including alternative models and misapplication of the scientific model. (Contains 1 table, 2 figures and 5 notes.)