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Ranger VII Photographs of the Moon 1964 NASA-JPL; First Successful US Lunar Spacecraft
🕑 Added 2019-06-10 02:10:27 +0000 UTCmore at http://quickfound.net/
Originally a public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
https://en.wikipedia.org/wiki/Ranger_7
Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/
Ranger 7 was the first space probe of the United States to successfully transmit close images of the lunar surface back to Earth. It was also the first completely successful flight of the Ranger program. Launched on July 28, 1964, Ranger 7 was designed to achieve a lunar-impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. The spacecraft carried six television vidicon cameras – two wide-angle (channel F, cameras A and B) and four narrow-angle (channel P) – to accomplish these objectives. The cameras were arranged in two separate chains, or channels, each self-contained with separate power supplies, timers, and transmitters so as to afford the greatest reliability and probability of obtaining high-quality video pictures. Ranger 7 transmitted over 4,300 photographs during the final 17 minutes of its flight. After 68.6 hours of flight, the spacecraft landed between Mare Nubium and Oceanus Procellarum. This landing site was later named Mare Cognitum. The velocity at impact was 1.62 miles per second, and the performance of the spacecraft exceeded hopes. No other experiments were carried on the spacecraft...
The first countdown on July 27 failed due to a defective battery in the Atlas and a problem with the ground guidance equipment. The next day, all went smoothly and Ranger 7 lifted off from LC-12 at 12:50 PM EST. The weather was clear and cloudless on this launch and Atlas staging was observed by tracking cameras. The expected propellant cloud enveloped the booster, but no anomalous events occurred this time. Thirty minutes after liftoff, the Agena restarted to boost Ranger 7 on a trajectory towards the Moon...
As Ranger 7 sped towards the surface of the Moon, TV camera performance remained normal. Images of the cratered lunar surface continued to filter back to JPL headquarters in Pasadena, California and finally, at 6:25, impact occurred and all signals from the probe ceased. In the JPL control room, there was "rapturous celebration". Ranger 7 had delivered the first close-distance imagery of the lunar surface and "more than anything, even the manned Mercury missions, had at last undone the sting Americans felt at Sputnik 1's launch".
The photographs returned from the probe found that the Moon was most likely "very craggy and rocky with debris everywhere"... Ranger 7's images did seem to suggest that it was solid enough.
Ranger 7 reached the Moon on 31 July. The F-channel began its one-minute warm-up 18 minutes before impact. The first image was taken at 13:08:45 UT at an altitude of 2110 km. Transmission of 4,308 photographs of excellent quality occurred over the final 17 minutes of flight. The final image taken before impact has a resolution of 0.5 meters. The spacecraft encountered the lunar surface in direct motion along a hyperbolic trajectory, with an incoming asymptotic direction at an angle of -5.57 degrees from the lunar equator. The orbit plane was inclined 26.84 degrees to the lunar equator. After 68.6 hours of flight, Ranger 7 impacted in an area between Mare Nubium and Oceanus Procellarum (subsequently named Mare Cognitum) at 10.6340°S 20.6771°W.[1] (The impact site is listed as 10.63 S, 20.66 W in the initial report "Ranger 7 Photographs of the Moon".) Impact occurred at 13:25:48.82 UT at a velocity of 2.62 km/s. The spacecraft performance was excellent and the success of the mission finally brought a turnaround in NASA's fortunes after the endless string of lunar probe failures since 1958.
Ranger 7 is credited for beginning the "peanut" tradition at NASA command stations. On the success of Ranger 7, someone in the control room was noticed eating peanuts – surely the reason the mission was successful. Since 1964 control rooms ceremonially open a container of peanuts for luck and tradition.
