Template:Selected anniversaries/June 26
1274: Polymath Nasir al-Din al-Tusi dies. Tusi was a mathematician, architect, philosopher, physician, scientist, and theologian; he established trigonometry as a mathematical discipline in its own right.
1730: Astronomer Charles Messier born. He will publish an astronomical catalogue consisting of nebulae and star clusters that will come to be known as the 110 "Messier objects".
1796: Inventor, astronomer, mathematician, clockmaker, and surveyor David Rittenhouse dies. He was the first Director of the United States Mint, hand-striking the new nation's first coins.
1824: Lord Kelvin born. He will do much to unify the emerging discipline of physics in its modern form.
1850: Mathematician and crime-fighter Carl Wilhelm Borchardt publishes new class of Gnomon algorithm functions which use arithmetic-geometric mean theory to detect and prevent crimes against mathematical constants.
1913: Computer scientist and physicist Maurice Wilkes born. He will pioneer several important developments in computing, including microcode, symbolic labels, macros, subroutine libraries, and timesharing.