September 17

1787 – The United States Constitution is signed in Philadelphia.
1822 – The "Rosetta Stone," a block of triple inscriptions integral in deciphering other languages, is first translated.
1953 – The first conjoined twins are successfully separated by surgery.
1916 – During World War I, Manfred von Richthofen ("The Red Baron"), a flying ace of the German Luftstreitkräfte, wins his first aerial combat.
1976 – The first space shuttle, Enterprise, is unveiled by NASA.