Resources

Most of the textbooks used in writing the guide have been mentioned in the About page. Here are some additional resources that you may find useful:

General

• This Drive contains all the sources used, and more. Many national and international olympiad papers too are available here.
• Sean Ken M. Galanza’s amazing astronomy handouts
• Kevin Zhou’s Physics Olympiad Handouts, mainly M6 and X3
• USAAAO Guide - Handouts for USAAAO and IOAA preparation
• Blogs by Armin Hodaei
• Celestial Sphere - A webapp to play with spherical diagrams
• Astronomy Olympiad Discord Server (AODS) - a community of astronomy enthusiasts and olympiad participants. Great place to ask questions, share resources, and connect with others who share your interest in astronomy.

Observation

• A Practical Handout for Olympiad by Ayush Tiwari
• Star Maps 101 and Practices by Fahim Rajit Hossain
• Learn the Sky - A YouTube channel with videos on finding constellations, planets and navigating the sky.
• Sky Academy - An android app which you can use to learn constellations, stars and messier objects.
• Stellarium Mobile App and Desktop App - A planetarium software that shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.
• BAAO Observational Handouts

Competitions and Olympiad Archives

• OAC - the Online Astronomy Competition
• Official IOAA Website
• Astronomy Olympiad Archives by Stefan Ivanov
• Astroarena - Contains all pre 2020 IOAA papers
• AstroSandbox - A website founded by Ukrainian IOAA participants, gives lectures, organizes events, manages clubs, composes our own astronomy tasks, as well as collects existing problems from Olympiads and public sources.
• USAAAO Archives - First Round and NAC papers of USA’s astronomy olympiad
• SAO Archives - Singapore Astronomy Olympiad past papers
• INAO Archives - India National Astronomy Olympiad past papers
• OAAO - the Online Astronomy and Astrophysics Olympiad

If you have any other resources that you think would be useful, feel free to share them in the resources channel on our Discord server.

Country-specific Advice

If you have represented your country in IOAA and would like to contribute a similar advice document for future participants from your country, please reach out to us on our Discord server.

References & Sources

AO Guide is built upon the foundational work of many excellent textbooks, research papers, and educational resources. These books were not written with IOAA in mind, but they’re wonderful in general!

Primary Textbooks

• Astronomy: Principles and Practice by A. E. Roy and D. Clarke
• Fundamental Astronomy by Hannu Karttunen et al.
• Fundamentals of Astronomy by Flavio Salvati
• Introduction to Cosmology by Barbara Ryden
• Foundations of Astrophysics by Barbara Ryden
• An Introduction to Modern Astrophysics by Bradley W. Carroll and Dale A. Ostlie
• A Problem book in Astronomy and Astrophysics by Aniket Sule

Data Sources

• International Astronomical Union (IAU) - Constants and definitions
• Wikipedia - For general reference and quick lookups (always cross-verify with primary sources)
• CODATA - Fundamental physical constants

A list of useful constants is provided at the end of the page.

Problem Sources

• Previous IOAA Problems (2007-2025) - Official competition problems and solutions
• National Astronomy Olympiads - Problems from various countries’ national competitions
• Physics Competitions - Adapted problems from IPhO, national physics olympiads, and physics contests
• Other Astronomy Competitions - Problems from regional astronomy contests and university-level competitions
• Original Problems - Custom problems designed specifically for IOAA preparation by us
• Research Literature - Adapted problems from peer-reviewed journals

Constants List