Ignazio Danti

Ignazio Danti (* April 1536 in Perugia, † October 19, 1586 in Alatri, also Egnatio or Egnazio Danti, born as Pellegrino Rainaldi Danti ) was an Italian mathematician, astronomer and cosmologist and cartographer.

Danti was born into a wealthy family from Perugia. His father Giulio was an architect and a pupil of Antonio da Sangallo the Elder. To form Dantis little is known, but he probably attended the University of Perugia. On March 7, 1555 Danti was included in the Dominican Order and took the religious name Ignatius. In 1562 he went to Florence. There he taught on behalf of his Order pupils in mathematics and science. In September 1563 he was invited by Cosimo I, Duke of Tuscany, part of a scientific project to cartography. Dantis brother Vincenzo Danti was a sculptor at Cosimo's court, so it is quite possible that it helped that to get the contract for the cartographic project. In the next few years he made over 30 cards. In 1574 he discovered the 11-day gap between the Julian calendar and the solar year. He then became an important advocate of the Gregorian calendar reform.

After the death of Cosimo Danti had to leave Florence in 1575, professor in Bologna. Here he was known by the gnomon he built in the Basilica of San Petronio. From 1580 he worked for Pope Gregory XIII. as a cartographer. In recognition, he was appointed in 1583 to the Bishop of Alatri.