The role of visualization and model-based reasoning has become increasingly significant in science education across a range of contexts. It is generally recognized that supporting learning in developing causal explanations for observed astronomical events presents considerable pedagogic challenge. Understanding the Sun's apparent movement across the sky requires a sophisticated interpretation of visuospatial relations. This study explores how preservice teachers employ models in reasoning about this phenomenon. It adopts a research methodology that attempts to capture the fine detail of learning using a range of strategies to determine student teachers' use of models in visuospatial reasoning. This included individual learners documenting their responses during taught sessions as part of the process of capturing their personal perceptions. Student reflections on their own learning were subsequently discussed during follow-up audiotaped interviews. The findings revealed four different models of visuospatial reasoning used by the student teachers and highlighted subtle differences between individuals. The ways participants used these to make sense of the phenomenon and how this contributes to our understanding of model-based reasoning in basic astronomy are discussed.