Vimana Purana, which today’s scientists have now started finding relevance in, had never contemplated the presence of gurutvakarshan, which was later called gravitational force? Do you think that writing a comprehensive purana on flying would have been possible without a precise understanding of gravitational force? A Sanskrit verse from Brahmagupta’s book Brahmasphutasiddhanta says, “A body falls towards the earth as it is the nature of the earth to attract bodies, just as it is the nature of water to flow.”