THIS DAY IN HISTORY

Year: 1975

Month Day: August 20

Viking 1 launched to Mars

Viking 1, an unmanned U.S. planetary probe, is launched from Cape Canaveral, Florida, on a mission to Mars.

On June 19, 1976, the spacecraft entered into orbit around Mars and devoted the next month to imaging the Martian surface with the purpose of finding an appropriate landing site for its lander. On July 20–the seventh anniversary of the Apollo 11 lunar landing–the Viking 1 lander separated from the orbiter and touched down on the Chryse Planitia region, becoming the first spacecraft to successfully land on the surface of Mars. The same day, the craft sent back the first close-up photographs of the rust-colored Martian surface.

In September 1976, Viking 2–launched only three weeks after Viking 1–entered into orbit around Mars, where it assisted Viking 1 in imaging the surface and also sent down a lander. During the dual Viking missions, the two orbiters imaged the entire surface of Mars at a resolution of 150 to 300 meters, and the two landers sent back more than 1,400 images of the planet’s surface.

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ALSO ON THIS DAY

Slavery in Jamestown

On this day in 1619, “20 and odd” Angolans, kidnapped by the Portuguese, arrive in the British colony of Virginia and are then bought by English colonists. The arrival of the enslaved Africans in the New World marks a beginning of two and a half centuries of slavery in North ...read more

Exiled Russian revolutionary Leon Trotsky is fatally wounded by an ice-ax-wielding assassin at his compound outside Mexico City. The killer—Ramón Mercader—was a Spanish communist and probable agent of Soviet leader Joseph Stalin. Trotsky died from his wounds the next day. Born in ...read more

During the Lebanese Civil War, a multinational force including 800 U.S. Marines lands in Beirut to oversee the Palestinian withdrawal from Lebanon. It was the beginning of a problem-plagued mission that would stretch into 17 months and leave 262 U.S. servicemen dead. In 1975, a ...read more

On the night of August 20, 1968, approximately 200,000 Warsaw Pact troops and 5,000 tanks invade Czechoslovakia to crush the “Prague Spring”—a brief period of liberalization in the communist country. Czechoslovakians protested the invasion with public demonstrations and other ...read more

Inventions & Science

On August 20, 1911, a dispatcher in the New York Times office sends the first telegram around the world via commercial service. Exactly 66 years later, the National Aeronautics and Space Administration (NASA) sends a different kind of message–a phonograph record containing ...read more

President Eisenhower approves a National Security Council paper titled “Review of U.S. Policy in the Far East.” This paper supported Secretary of State Dulles’ view that the United States should support Vietnamese prime minister Ngo Dinh Diem, while encouraging him to broaden ...read more

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On August 20, 1920, seven men, including legendary all-around athlete and football star Jim Thorpe, meet to organize a professional football league at the Jordan and Hupmobile Auto Showroom in Canton, Ohio. The meeting led to the creation of the American Professional Football ...read more

U.S. Presidents

On this day in 1833, future President Benjamin Harrison is born in North Bend, Ohio. Politics had long been the Harrison family business. At the time of his birth, Harrison’s father was serving Ohio in the United States House of Representatives, while his grandfather, William ...read more

Westward Expansion

Sergeant Charles Floyd dies three months into the voyage of Meriwether Lewis and William Clark, becoming the only member of the Corps of Discovery to die during the journey. Lewis and Clark left St. Louis the previous May, heading up the Missouri River with a party of 35 men, ...read more

Art, Literature, and Film History

On August 20, 1918, Jacqueline Susann, the author of Valley of the Dolls, the 1966 mega-hit novel about the showbiz lives of three women (reportedly modeled in part after Judy Garland, Marilyn Monroe and Grace Kelly), is born in Philadelphia, Pennsylvania. Like her characters in ...read more

Lyle and Erik Menendez shoot their parents, Jose and Kitty, to death in the den of the family’s Beverly Hills, California, home. They then drove up to Mulholland Drive, where they dumped their shotguns before continuing to a local movie theater to buy tickets as an alibi. When ...read more

This Day in History

In the face of rising anti-Soviet protests in Czechoslovakia, Soviet troops (backed by troops from other Warsaw Pact nations) intervene to crush the protest and restore order. The brutal Soviet action shocked the West and dealt a devastating blow to U.S.-Soviet relations. The ...read more

New YorkTribune editor Horace Greeley publishes a passionate editorial calling on President Abraham Lincoln to declare emancipation for all slaves in Union-held territory. Greeley’s blistering words voiced the impatience of many Northern abolitionists; but unbeknownst to Greeley ...read more

On August 20, 1794, General “Mad Anthony” Wayne proves that the fragile young republic can counter a military threat when he puts down Shawnee Chief Blue Jacket’s confederacy near present-day Toledo, Ohio, with the newly created 3,000-man strong Legion of the United States at the ...read more