The study investigates students' ability to analyze visual literacy and digital literacy through open-ended inquiry activities with astronomical observations and Heaven View application. The investigation consists of assignments for students to carry out six different variations of observational activities. Supervision is given in introductory astronomy lectures before and after using open-ended inquiry as direct observation and indirect observation activities. We discuss the implicits for open-ended inquiry learning that encourage students to participate in observational activities. Students are expected to develop several 21st century skills through an open-ended inquiry process, including visual-digital literacy. A pretest-posttest control group design with an open-ended inquiry model was applied to the experimental group and a direct instruction model to the control group. This study uses inferential statistical parametric methods, using ANCOVA. Students' visual-digital literacy data were obtained using the pretest and posttest. The results showed that a statistically significant difference between open-ended inquiry through astronomical laboratory observations assisted by Heaven View application compared to direct model recognition. Students' visual-digital literacy has increased due to the application of this learning model. The implications of this research can encourage students' visual-digital science literacy. Other educators can adopt open-ended learning experiences through the Heaven View app-assisted astronomical observation labs to promote visual-digital literacy in science.