Apollo 11: first manned lunar landing
The Apollo 11 lunar module touches down in the Sea of Tranquility, a flat plain on the moon. Astronaut Neil Armstrong is the first human being to set foot on another body in the solar system, followed by “Buzz” Aldrin; the two spend roughly two and a half hours on the moon and gather nearly 50 pounds of samples of lunar soil and rock. This feat effectively ends the Cold War space race, though both the United States and the Soviet Union continue their lunar efforts: more Apollo missions are still on the schedule, and the Soviet continue trying to mount a successful launch of their giant N1 rocket.
This mission is dramatized in the Mare Tranquilitatis episode of HBO’s 1998 series From The Earth To The Moon.
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Viking 1 makes a soft landing on Mars, the first spacecraft to do so intact (the Soviet space program had been attempting to put landers on Mars, some of them including rudimentary rovers, since 1962). It successfully transmits the first picture from the Martian surface back to Earth within seconds, and successfully gathers soil samples for analysis. Viking 1’s orbiter mothership will later shut down in 1980, but the lander itself functions until 1982. Viking 1’s landing takes place on the seventh anniversary of the first manned moon landing.
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The week-long national syndication window opens for 
The seventh episode of Return To Jupiter airs on the Australian Broadcasting Corporation. Co-produced by ABC and Japanese network NHK, this children’s sci-fi series stars Sonia Todd (Home And Away) and David Wenham (The Lord Of The Rings trilogy).
Sci-Fi Channel airs the 55th episode of the science fiction series Sliders, starring Jerry O’Connell, Cleavant Derricks, Kari Wuhrer, and Charlie O’Connell.
A day short of exactly 38 years since the capsule 
Pay cable channel Showtime airs the 91st episode of Stargate SG-1. John de Lancie (Star Trek: The Next Generation) guest stars.
James Doohan, the actor known to millions as the original Star Trek’s Chief Engineer Scott, dies at the age of 85. A veteran TV and radio actor who also led Canadian troops during D-Day in World War II, he tried out a number of accents for what was originally a rather non-specific engineer character for Star Trek’s first season before settling on a Scottish accent; even after the series ended, his involvement with Star Trek continued, and he provided nearly every male voice outside of the show’s regular characters in the short-lived animated Star Trek series before reprising the role of Scotty in the first seven Star Trek films and a fan-favorite episode of Star Trek: The Next Generation. He was diagnosed with Alzheimer’s Disease last year, and made a farewell appearance at Star Trek convention a few months later, and received a star on the Hollywood Walk of Fame as well.
Film Score Monthly releases an expanded CD edition of James Horner’s soundtrack from 
Blue Origin, the private spaceflight company founded and owned by Amazon.com founder Jeff Bezos, launches its first fully-crewed New Shepard capsule into suborbital space. Aboard are Bezos, his brother Mark Bezos, Mercury 13 astronaut candidate Wally Funk (at 82, the oldest human to have traveled in space to date), and Oliver Daemen (at 18, the youngest human space traveler to date); the vehicle is fully automatic and has no pilots (or, indeed, control systems for pilots) aboard, with the flight lasting ten minutes from liftoff to landing under parachute. This is the first crewed spaceflight launched from Blue Origin’s Texas facility. As both the New Shepard booster and crew capsule are reusable, the hardware has all been previously flown.
The CW airs the 150th episode of The Flash, a modern-day reboot of DC Comics’ superhero starring Grant Gustin. This is the seventh season finale.
The CW airs the 13th episode of Superman & Lois, starring Tyler Hoechlin, Elizabeth Tulloch, Jordan Elsass, and Alex Garfin.