Space has fascinated and intrigued humans of all ages since time immemorial, and continues to do so today. The natural curiosity is engaged when looking up into the sky, notice patterns among celestial objects such as the Sun, Moon, and stars, and wonder. Scientific understanding of those patterns has progressed immensely over the span of human existence, and today the "Next Generation Science Standards" (NGSS) incorporates a rich focus on those celestial phenomena from the very earliest years in school. As students get older, through elementary school and then into middle and high school, the NGSS carefully and thoughtfully offers standards that incorporate space science (and other domains of science) learning progressions, increasingly targeting more sophisticated and nuanced student understanding as students develop. To best develop student thinking along these progressions, it is important for students to acquire a solid foundation of experiences and understanding. This article focuses on establishing a strong beginning to that foundation of space science for primary elementary students. The authors present a lesson where students explore Earth and space science by modeling and observing patterns. [For Part 2, "Seeing the Solar System through Two Perspectives. Part 2 of a Series Focusing on Learning Progressions," see EJ1115171.]