Gian Lorenzo Bernini finishes construction of the balconies required above the large niches in the pillars of Saint Peters Basilica for the exhibition on special occasions of the most venerated relics in the church.
Extract a cover letter from Leonardo da Vinci to Sultan Bejazet (or Beyazid) II offering his services. This is dated by Charles Nicholl to July 3, 1503.
> I, your servant, have heard about your intention to build a bridge from Stanboul to Galata, and that you have not done it because no man can be found capable of it. I, your servant, know how. I would raise it to the height of a building, so that no one can pass over it because it is so high ... I will make it so that a ship can pass under it even with its sails hoisted.... I would have a drawbridge so that when one wants one can pass on to the Anatolian coast.... May God make you believe these words, and consider this servant of yours always at your service.
Orbital calculations suggest that on this day, Pluto moves outside Neptune's orbit, remaining there for 233 years.