In his work, 'Epitome of the essence of calculation', ninth century Indian mathematician Mahāvīra characterised mathematical knowledge as ‘an ocean of calculation’. Indeed, the astral sciences in the Indian subcontinent – that is, mathematics, astronomy, and related disciplines – have been flourishing for over two and a half millennia, and this culture of inquiry has produced insights and techniques that are central to many of our scientific practices today, such as the base ten decimal place value system and trigonometry. We consider a selection of mathematical highlights from this scientifically dynamic tradition and account for some of the challenges faced by historians of mathematics in the task of accounting for the scientific legacy of this extensive and rich culture of inquiry.