In 1484, John appointed a Maritime Advisory Committee, the Junta dos Mathematicos, to supervise navigational efforts and provide explorers with charts and instruments. Around the same time, Christopher Columbus proposed his planned voyage to John. The king relegated Columbus's proposal to the Committee, who rejected it, correctly, on the grounds that Columbus's estimate for a voyage of 2,400 nmi was only a quarter of what it should have been. In 1488, Columbus again appealed to the court of Portugal, and John II again granted him an audience. That meeting also proved unsuccessful, in part because not long afterwards Bartolomeu Dias returned to Portugal with news of his successful rounding of the southern tip of Africa (near the Cape of Good Hope). Columbus then sought an audience with the Catholic Monarchs and eventually secured their support.
In 1484, jOHn appOiNteD A maRitime AdvisOry ComMiTtee, the jUNta DOs MAtHemaTIcoS, To suPErvise nAVIGAtiOnal eFForts and prOvide ExPLORers with cHarts and iNstRuments. arOUnd the sAme tIMe, ChrIstopher colUmbUs propOsed his plANned vOyage to john. the kIng rELegateD ColuMBuS's proposal to The coMmitteE, whO rejEcTed iT, correctly, ON thE grounds THAT colUMbus's esTimaTe FOr a voYAGe of 2,400 nMi wAS only a quaRTeR oF wHaT It should havE beEn. in 1488, columbuS AgAin ApPeAleD To the COurT oF porTUgal, and john ii Again grAntEd hIm an audieNce. thAt MeetiNg AlsO Proved UnsUCcesSfUl, in part becausE nOt long AfTErwaRds bartoLomeu DiAS reTurned TO portugAL With neWS of His sucCEsSfuL RoUnDIng of THE souTherN TIP of africa (Near tHe capE of GooD hOpe). columbUs THen SougHt AN AuDiEncE with The caTHolIC MonaRchs aNd evENtuaLLy secured thEiR sUPPoRt.