The United States Army, and a retinue of scientists who have participated in the top-secret Manhattan Project to create a workable atomic bomb before the then-hostile governments of Germany or Japan can do so, carry out the first detonation of a nuclear weapon in human history, generating a massive explosion with a yield of 22 kilotons of TNT. This is the final test before the deployment of two nuclear weapons in the United States’ war with Japan mere weeks later. Manhattan Project scientists present to witness the test include Robert Oppenheimer, Richard Feynman, Enrico Fermi, and John von Neumann.
The 
Apollo 11 lifts off, with astronauts Neil Armstrong, Buzz Aldrin and Michael Collins aboard. This is the first mission scheduled to attempt a landing on the moon, with Armstrong and Aldrin aboard the lunar module while Collins remains in orbit in the command/service module.
The 
Atari releases its second arcade game: the very first video racing game, 
The 
After grueling location shooting in Tunisia and lengthy studio filming at Elstree Studios in England, principal photography wraps up on George Lucas’ 
NASA launches Landsat 4, the fourth Landsat Earth resource observation satellite and the first to be redesigned from the ground up (previous Landsats had been based on NASA’s Nimbus satellites from the 1960s and ’70s). For the first time, Landsat data processing and distribution is handled by another government agency, the U.S. Geological Survey, which partners with NASA on all future Landsat satellites. Landsat 4 is the first Landsat to link up to NASA’s TDRS (Tracking & Data Relay Satellite) system, thus enabling real-time data transmission to Earth even when Landsat 4 isn’t passing over a ground station. Landsat 4 remains operational through the end of 1993.
Its collision with the solar system’s largest planet predicted over a year in advance, the fragments of Comet Shoemaker-Levy 9 begin impacting Jupiter’s atmosphere in an astronomical event lasting six days. With Earth-based telescopes watching, as well as cameras and instruments on the Hubble Space Telescope, Galileo and even Voyager 2, huge explosions are witnessed as the cometary chunks slam into Jupiter’s southern hemisphere at over 200,000 miles per hour, leaving dark “scars” larger than the diameter of Earth visible on the planet’s atmosphere and releasing more heat than the surface of the sun. Galileo is still over a year away from arriving at Jupiter.
Premium cable channel Showtime airs the 17th episode of The Outer Limits, a revival of Leslie Stevens’ 1960s science fiction anthology series. Marlee Matlin and Larry Drake guest star.
The ninth episode of the adult-themed science fiction anthology series Perversions Of Science, based largely on stories published in Weird Science magazine, premieres on cable network HBO.
Sony Records’ Work imprint releases former Crowded House frontman 
Sci-Fi Channel airs the 74th episode of the science fiction series Sliders, starring Cleavant Derricks, Kari Wuhrer, Robert Floyd, and Tembi Locke.
Pay cable channel Showtime premieres the 
Sci-Fi Channel premieres the 
Sci-Fi Channel airs 
Sources within NBC reveal to the media that a revival of the ’80s science fiction series V, being written by its creator, Kenneth Johnson, is languishing in a development hell from which neither the network nor its corporate cousin under the Vivendi-Universal umbrella, the Sci-Fi Channel, wants to rescue it. The project, titled V: The Second Generation, simply hasn’t excited anybody enough to greenlight it past the script stage. NBC has passed on V for now, and even Sci-Fi has turned back the lizard invasion. NBC’s executive in charge of miniseries and movies-of-the-week urges Johnson to continue rewrites rather than abandoning ship.
Syfy airs the 45th episode of the science fiction series Eureka, starring Colin Ferguson, Salli Richardson-Whitfield, and Joe Morton. James Callis (Battlestar Galactica) and Tembi Locke (Sliders) guest star.
Launched in 2007, NASA’s unmanned space probe Dawn enters orbit of Vesta, one of the largest bodies in the main asteroid belt between Mars and Jupiter. Over time, the mission plan calls for Dawn to spiral down to lower orbits to explore and map Vesta from orbit, trying to determine what secrets the large asteroid has about the earliest days of the solar system. If all goes well, Dawn will remain at Vesta until 2012, and will depart to explore another asteroid, Ceres, arriving there in 2015.
A two-man spacewalk outside the International Space Station is called off when water begins collecting inside the helmet of astronaut Luca Parmitano’s spacesuit. Originally scheduled as a six-and-a-half-hour maintenance spacewalk, the EVA is called off at one hour and the astronauts make a hasty return to the airlock. Once inside, an estimated half liter of water is found inside Parmitano’s space helmet; the remainder of the tasks scheduled for this spacewalk are rescheduled for a later EVA.
British actor Trevor Baxter, best known in genre circles for a one-off appearance in the 1970s 
In a specially shot trailer aired after BBC1’s live coverage of the Wimbledon men’s tennis finals, the first female Doctor Who is unveiled in the form of actress Jodie Whittaker (Broadchurch, Black Mirror, Attack The Block). Her first appearance in the role proper will presumably take place at the end of outgoing star Peter Capaldi’s final episode, to be aired on Christmas Day 2017. The transition to a new Doctor also includes the transition to new showrunner Chris Chibnall, whose first season will be broadcast in 2018. 
Oscar-winning actor Martin Landau, a fixture of genre TV and movies since the late 1950s, dies at the age of 89. The star of such series as Mission: Impossible and 
Pioneering horror film director George A. Romero dies at the age of 77 after a battle with lung cancer. In 1968, his low-budget shocker Night Of The Living Dead all but gave birth to the zombie horror genre. Some of his later films attempted to tackle different subject matter, meeting with box office indifference until he returned to the zombie genre with Dawn Of The Dead (1976), which earned back more than 100 times its production budget. High-profile works after that included the Stephen King-written Creepshow (1982), Monkey Shines (1988), and a third film in his zombie cycle, Day Of The Dead (1985). Sticking this time with his connection to the genre, Romero continued to be involved in spinoffs for comics, internet shorts, and further films, including Road Of The Dead, a movie he promoted shortly before his death. His movies remain immensely influential in the horror genre.