What is the main objective of GAGAN satellite?

Option 1 -> GAGAN (GPS Aided GEO Augmented Navigation) is designed to enhance satellite navigation accuracy and reliability over Indian airspace.

Option 2 -> Remote sensing is the purpose of satellites like Resourcesat and Cartosat, not GAGAN.

Option 3 -> This describes astronomy missions like AstroSat, which study celestial objects, not navigation satellites.

Option 4 -> Communication satellites like GSAT series serve this purpose, not GAGAN.

Hence, Option 1: Provide satellite-based navigation services -> GAGAN is India's satellite-based augmentation system jointly developed by ISRO and AAI to provide accurate navigation services, primarily for civil aviation, by augmenting GPS signals over Indian Flight Information Region (FIR) -> correct