The paper discusses Husserl’s “mathematization of the world”, linked with Galileo Galilei and his heliocentric model. The rediscovery of the heliocentric system was fundamental for the formation of ideal objectivity and for a set of relations between natural sciences and the life-world, as also shown by Umberto Eco - who unveils the connections between Galileo's idealisation of the physical body and the invention of the Aristotelian telescope as a means to create ideal subjectivity.