<p>The Singapore Astronomy Olympiad (SAO) is a national competition in astronomy and astrophysics that selects candidates to represent Singapore at the International Olympiad on Astronomy and Astrophysics (IOAA). Modelled on the IOAA syllabus, it runs in two rounds — an open Round 1 and an invitation-only Round 2 for the top scorers.</p><ul><li>Eligibility: students under 20 years of age (as of 1 July) who have not exceeded Grade 12 or equivalent.</li><li>Round 1 (2026): 9 March, 16:00–18:00 — a 2-hour computerised test of 50 multiple-choice questions, sat in the candidate's school or at a centralised facility.</li><li>Round 2 (2026): 14 March at Hwa Chong Institution — a 4-hour paper covering short and long answer questions, data analysis, and practical/observational astronomy.</li><li>Top five medallists represent Singapore at the IOAA; only Singapore citizens and permanent residents are eligible for the national team.</li><li>Singapore won 4 Gold and 1 Bronze at the 18th IOAA in 2025, its best showing in nearly 20 years; the 19th IOAA will be in Hanoi in October 2026.</li></ul>