TODAY'S HISTORY: In 1952, Puerto Rico became a self-governing U.S. commonwealth.
In 1978, Louise Joy Brown, the first baby to be conceived via in vitro fertilization, was born in Greater Manchester, England.
In 2005, two major unions, the Teamsters and the Service Employees International Union, withdrew from the AFL-CIO.
In 2010, the website WikiLeaks released the "Afghan War Diary," containing more than 75,000 secret documents from the United States' war in Afghanistan.
TODAY'S BIRTHDAYS: Henry Knox (1750-1806), first U.S. secretary of war; Maxfield Parrish (1870-1966), painter/illustrator; Eric Hoffer (1902-1983), philosopher; Rosalind Franklin (1920-1958), biophysicist; Estelle Getty (1923-2008), actress; Walter Payton (1954-1999), football player; Iman (1955- ), model/actress; Thurston Moore (1958- ), musician; Matt LeBlanc (1967- ), actor; Lauren Faust (1974- ), animator.
TODAY'S FACT: The Viking Orbiter 1 spacecraft, while searching for potential landing sites for the Viking 2 Lander, snapped the famous "Face on Mars" photo of the planet's surface on this day in 1976.
TODAY'S SPORTS: In 1976, American Edwin Moses ran in his first international track and field event at the Montreal Olympics -- the 400m hurdles -- and won a gold medal, with a record-setting time of 47.64 seconds.
TODAY'S QUOTE: "The less justified a man is in claiming excellence for his own self, the more ready he is to claim all excellence for his nation, his religion, his race or his holy cause." -- Eric Hoffer, "The True Believer"
TODAY'S NUMBER: 3.4 million -- approximate combined membership of the Teamsters and the Service Employees International unions in 2018.
TODAY'S MOON: Between last quarter moon (July 24) and new moon (July 31).