text: Nā te 130 AD, o Ptolemy, i awea e ngā Hipparchus me ngā Babylonian, e whakamahi ana i tētahi tohu mō te 0 (he porohita iti me tētahi paerua roa) i roto i tētahi pūnaha tatauranga momo me te whakamahi i ngā tau Kariki reta.