Answer) The astronomy Olympiad program follows the following 5 stages:
Stage I: National Standard Examination in Astronomy (NSEA).
Stage II: Indian National Astronomy Olympiad (INAO),
Stage III: Orientation cum Selection Camp (that is OCSC) in astronomy,
Stage IV: Pre-departure Training Camp ( that is PDT) for IOAA,
Stage V: International Olympiad in Astronomy and Astrophysics (that is IOAA).