In earth science courses, the starry sky, the solar system and the universe have always been difficult for our school students to understand because their scale exceeds imagination. Fortunately, there are many videos on the Internet that can help students understand the mysteries of the universe. One of the interesting things is that "constellations are actually just projections that humans see from the earth and imagine." The main stars in the same constellation are never on the same plane. They are often far apart from each other, but they only look similar to each other on the earth. , which has been "elaborated" by humans, from dots and connections to weaving the story of constellations. In addition, "projection" has a similar concept in art, that is, "perspective technique" and the opposite "anti-perspective". Perspective was during the Renaissance, when artists began to create a space with almost real depth on a flat surface, or In indoor and outdoor spaces, reverse perspective is used to create a "realistic" picture that can only be seen from a single perspective. Viewed from other places, the picture will be distorted and unsightly. Therefore, from the three-dimensional to three-dimensional transformation of constellations, to the two-dimensional to three-dimensional space transformation in visual art, after many discussions between the four of them, they finally found the connection between the subjects and planned the course. However, the epidemic worsened and the originally scheduled visit Activities and coursework have been forced to stop or change, and classes have been switched to online classes. Joint group creations and activities have also been cancelled, allowing students to gradually shift from borrowing positions and observing shadows in life (projection, three-dimensional to two-dimensional) and then adding Imagination creates.