Astronomers for Planet Earth: tackling the climate crisis from the unique perspective of astronomy

Astronomers for Planet Earth (A4E) is a global, volunteer-based network of more than 2000 astronomers in 84 countries, from students and amateurs to professionals, brought together by a shared goal: tackling the climate crisis from the unique perspective of astronomy.Since its founding in 2019, A4E has been working to share the powerful view astronomers have of Earth. We, as astronomers, know how rare life on a planet is. We, as astronomers, know that there is no planet B. This perspective not only helps communicate the urgency of the climate crisis, but also reminds us of what is at stake.A4E work takes many forms. We focus on outreach and education, creating and sharing tools to help communicate and teach on climate change. We also foster a strong sense of community among members, united by shared values around justice, sustainability, and the preservation of life on Earth, and driven by our passion for astronomy. Environmental sustainability, accessibility, inclusiveness, and social justice are deeply interconnected, and this is reflected in both our diverse membership and the wide range of our activities, from public engagement and educational resources to collaboration with professional astronomers and the development of tools to measure and reduce the environmental impact of our field. Our projects and efforts are all carried out voluntarily. In this talk, we will explain how A4E is structured and what drives our work, showing how our values align with the principles of open planetary science, particularly when it comes to sharing knowledge, building community, and creating accessible resources. We will highlight recent projects and milestones, and explore how collaborative efforts can amplify impact. Finally, we will suggest concrete ways that individuals, whether students, astronomers, or institutions, can get involved.