AO Guide
A free, online, and comprehensive guide to mastery of Astronomy Olympiads with structured content, practice problems, and community resources.
About AO Guide
AO Guide is a free, online, and comprehensive guide designed specifically for students preparing for the International Olympiad on Astronomy and Astrophysics (IOAA). Created by Lilian (a PROMYS 2025 alumnus) and me, this guide fills a critical gap in astronomy education resources.
The main vision behind AO Guide is to be complete yet concise: containing exactly what students need for IOAA preparation, no more and no less. Rather than forcing students to jump between massive textbooks and scattered handouts, AO Guide provides a unified, modern resource that emphasizes understanding over mere memorization.
Core Features
Complete & Structured Curriculum
The guide covers six major domains of astronomy:
- Positional Astronomy: Master celestial coordinate systems, timekeeping, and the art of mapping the sky—essential for precise astronomical observation and navigation
- Photometry: Explore the measurement of light from celestial objects, magnitude systems, filters, and techniques that reveal the universe’s brightness and color
- Celestial Mechanics: Understand the gravitational dynamics of planets, moons, and artificial satellites. Analyze orbits, perturbations, and celestial motion mathematics
- Stellar Astrophysics: Delve into the structure, evolution, and end states of stars. From nuclear fusion to supernovae
- Galaxies and Cosmology: Explore the formation, evolution, and large-scale structure of galaxies, plus fundamental questions about the universe’s history
- Practical Astronomy: Develop essential skills in analyzing astronomical data, interpreting results, statistical methods, navigation, and observation
Conceptual Learning Approach
- Understanding Over Memorization: Each section is crafted to build intuition and analytical thinking
- Step-by-Step Derivations: Clear mathematical progressions that show how concepts connect
- Real Problem-Solving Practice: Extensive practice problems and worked examples with solutions
- Exam Strategies: Practical guidance for tackling olympiad-style questions
Visual & Interactive Content
- High-Quality Diagrams: Complex concepts visualized through professional illustrations
- Mathematical Rigor: Equations rendered beautifully with KaTeX for clarity
- Interactive Elements: Eye-catching components that help internalize complex ideas
- Accessible Design: Optimized for all devices with a distraction-free interface
Community-Driven Development
- Living Document: Continuously updated with new problems, explanations, and improvements based on user feedback
- Global Community: Built by and for the international astronomy Olympiad community
- Open Contribution: Contributors welcome - problems, explanations, improvements all appreciated
- Creative Commons License: Released under CC BY-NC-SA 4.0, free for educational use
Why This Exists
Astronomy Olympiads aren’t about memorizing formulas; they’re about:
- Really understanding how things work
- Thinking through problems step by step
- Having the confidence to tackle novel challenges
- Building analytical thinking skills
AO Guide is built to help students develop these skills through targeted, well-explained content and extensive problem-solving practice. Most importantly, it’s completely free and open to the global community, reflecting the creators’ belief that good education resources should be accessible to everyone.
Getting Involved
The project welcomes contributions from:
- Fellow students who spot errors or improvements
- Educators with suggestions for clarity or content
- Anyone interested in sharing quality problems or explanations
- Contributors wanting to improve the code or hosting
Visit the GitHub repository to contribute or join the community on Discord.