India is hosting the 18th International Olympiad on Astronomy and Astrophysics (IOAA) in Mumbai from August 11 to 21, with over 300 students from 64 countries participating. Organised by the Homi Bhabha Centre for Science Education (HBCSE), the event kicks off with an opening ceremony on August 12. The Olympiad includes theoretical, observational, and data analysis rounds.