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Apollo 11 missing tapes
The Apollo 11 missing tapes were those that were recorded from Apollo 11's slow-scan television (SSTV) telecast in its raw format on telemetry data tape at the time of the first Moon landing in 1969 and subsequently lost.
The data tapes were used to record all transmitted data (video as well as telemetry) for backup.
To broadcast the SSTV transmission on standard television, NASA ground receiving stations performed real-time scan conversion to the NTSC television format. The moonwalk's converted video signal was broadcast live around the world on July 21, 1969 (2:56 UTC). At the time, the NTSC broadcast was recorded on many videotapes and kinescope films. Many of these low-quality recordings remain intact. As the real-time broadcast worked and was widely recorded, preservation of the backup video was not deemed a priority in the years immediately following the mission. In the early 1980s, NASA's Landsat program was facing a severe data tape shortage and it is likely the tapes were erased and reused at this time.
A team of retired NASA employees and contractors tried to find the tapes in the early 2000s but was unable to do so. The search was sparked when several still photographs appeared in the late 1990s that showed the visually superior raw SSTV transmission on ground-station monitors. The research team conducted a multi-year investigation in the hopes of finding the most pristine and detailed video images of the moonwalk. If copies of the original SSTV format tapes were to be found, more modern digital technology could make a higher-quality conversion, yielding better images than those originally seen. The researchers concluded that the tapes containing the raw unprocessed Apollo 11 SSTV signal were erased and reused by NASA in the early 1980s, following standard procedure at the time.
Although the researchers never found the telemetry tapes, they did discover the best visual quality NTSC videotapes as well as Super 8 movie film taken of a video monitor in Australia, showing the SSTV transmission before it was converted. These visual elements were processed in 2009, as part of a NASA-approved restoration project of the first moonwalk. At a 2009 news conference in Washington, D.C., the research team released its findings regarding the tapes' disappearance. They also partially released newly enhanced footage obtained during the search. Lowry Digital completed the full moonwalk restoration project in late 2009.
Apollo 11 was the spaceflight that landed the first two people on the Moon. Neil Armstrong became the first person to step onto the lunar surface on July 21, 1969, at 02:56 UTC; Buzz Aldrin joined him 19 minutes later. Only limited radio bandwidth was available to transmit the video signal from the lunar landings, which needed to be multiplexed with other communication and telemetry channels beamed from the Lunar Module Eagle, back to Earth. Therefore, Apollo 11's moonwalk video was transmitted from the Apollo TV camera in a monochrome SSTV format at 10 frames per second (fps) with 320 lines of resolution, progressively scanned. These SSTV signals were received by radio telescopes at Parkes Observatory in Australia, the Goldstone tracking station in California, and Honeysuckle Creek tracking station, also in Australia. The camera's video format was incompatible with existing NTSC, PAL, and SECAM broadcast television standards. It needed to be converted before it could be shown on broadcast television networks. This live conversion was crude, essentially using a video camera pointing at a high-quality 10-inch (25 cm) TV monitor.
Since the camera's scan rate was much lower than the approximately 30 fps for NTSC video, the television standard used in North America at the time, a real-time scan conversion was needed to be able to show its images on a regular TV set. NASA selected a scan converter manufactured by RCA to convert the black-and-white SSTV signals from the Apollo 7, 8, 9 and 11 missions.
When the Apollo TV camera radioed its images, the ground stations received its raw unconverted SSTV signal and split it into two branches. One signal branch was sent unprocessed to a 14-track analog data tape recorder, where it was recorded onto 14-inch (36 cm) diameter reels of one-inch-wide (25 mm) analog magnetic data tapes at 120 inches (3.0 m) per second. The other raw SSTV signal branch was sent to the RCA scan converter, where it was processed into an NTSC broadcast television signal.
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Apollo 11 missing tapes
The Apollo 11 missing tapes were those that were recorded from Apollo 11's slow-scan television (SSTV) telecast in its raw format on telemetry data tape at the time of the first Moon landing in 1969 and subsequently lost.
The data tapes were used to record all transmitted data (video as well as telemetry) for backup.
To broadcast the SSTV transmission on standard television, NASA ground receiving stations performed real-time scan conversion to the NTSC television format. The moonwalk's converted video signal was broadcast live around the world on July 21, 1969 (2:56 UTC). At the time, the NTSC broadcast was recorded on many videotapes and kinescope films. Many of these low-quality recordings remain intact. As the real-time broadcast worked and was widely recorded, preservation of the backup video was not deemed a priority in the years immediately following the mission. In the early 1980s, NASA's Landsat program was facing a severe data tape shortage and it is likely the tapes were erased and reused at this time.
A team of retired NASA employees and contractors tried to find the tapes in the early 2000s but was unable to do so. The search was sparked when several still photographs appeared in the late 1990s that showed the visually superior raw SSTV transmission on ground-station monitors. The research team conducted a multi-year investigation in the hopes of finding the most pristine and detailed video images of the moonwalk. If copies of the original SSTV format tapes were to be found, more modern digital technology could make a higher-quality conversion, yielding better images than those originally seen. The researchers concluded that the tapes containing the raw unprocessed Apollo 11 SSTV signal were erased and reused by NASA in the early 1980s, following standard procedure at the time.
Although the researchers never found the telemetry tapes, they did discover the best visual quality NTSC videotapes as well as Super 8 movie film taken of a video monitor in Australia, showing the SSTV transmission before it was converted. These visual elements were processed in 2009, as part of a NASA-approved restoration project of the first moonwalk. At a 2009 news conference in Washington, D.C., the research team released its findings regarding the tapes' disappearance. They also partially released newly enhanced footage obtained during the search. Lowry Digital completed the full moonwalk restoration project in late 2009.
Apollo 11 was the spaceflight that landed the first two people on the Moon. Neil Armstrong became the first person to step onto the lunar surface on July 21, 1969, at 02:56 UTC; Buzz Aldrin joined him 19 minutes later. Only limited radio bandwidth was available to transmit the video signal from the lunar landings, which needed to be multiplexed with other communication and telemetry channels beamed from the Lunar Module Eagle, back to Earth. Therefore, Apollo 11's moonwalk video was transmitted from the Apollo TV camera in a monochrome SSTV format at 10 frames per second (fps) with 320 lines of resolution, progressively scanned. These SSTV signals were received by radio telescopes at Parkes Observatory in Australia, the Goldstone tracking station in California, and Honeysuckle Creek tracking station, also in Australia. The camera's video format was incompatible with existing NTSC, PAL, and SECAM broadcast television standards. It needed to be converted before it could be shown on broadcast television networks. This live conversion was crude, essentially using a video camera pointing at a high-quality 10-inch (25 cm) TV monitor.
Since the camera's scan rate was much lower than the approximately 30 fps for NTSC video, the television standard used in North America at the time, a real-time scan conversion was needed to be able to show its images on a regular TV set. NASA selected a scan converter manufactured by RCA to convert the black-and-white SSTV signals from the Apollo 7, 8, 9 and 11 missions.
When the Apollo TV camera radioed its images, the ground stations received its raw unconverted SSTV signal and split it into two branches. One signal branch was sent unprocessed to a 14-track analog data tape recorder, where it was recorded onto 14-inch (36 cm) diameter reels of one-inch-wide (25 mm) analog magnetic data tapes at 120 inches (3.0 m) per second. The other raw SSTV signal branch was sent to the RCA scan converter, where it was processed into an NTSC broadcast television signal.