The Apollo 11 missing tapes are missing slow-scan television (SSTV) recordings of the lunar transmissions broadcast during the Apollo 11 moonwalk, which was the first time human beings walked on the Moon. The tapes carried SSTV and telemetry data recorded onto analog data recording tape. The SSTV data was recorded as a backup against any failure of the live television broadcasts.[1] To allow broadcast of the SSTV transmission on standard television, a real-time conversion from SSTV format was done. The converted video of the moonwalk was broadcast live around the world on July 21, 1969 (UTC). Many videotapes and kinescopes were made of this broadcast as it happened, and these have never been missing.[2] Meanwhile, the missing tapes which carried recordings of the SSTV signal as transmitted from the Moon, but before undergoing scan conversion, are believed to have been erased and reused by NASA, along with many thousands of other tapes. (NASA was faced with a shortage of quality data tapes in the early 1980s due to a change in the manufacturing process in the mid 1970s. This caused tapes that were no longer needed to be reused.)[1] If the original SSTV format tapes were found, modern technology could be easily and cheaply used to make a higher-quality conversion, yielding better images than those originally seen. There are several still photographs, along with a few short segments of super 8 movie film taken of a video monitor in Australia, which show the SSTV transmission before it was converted.
In 2009 NASA gathered old copies of the converted video and paid to have them processed by Lowry Digital. These restorations were released in 2010.
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Only limited bandwidth was available to transmit the video signal, which needed to be multiplexed with other communication and telemetry channels beamed from the Lunar Module back to the Earth, so video of the Apollo 11 moonwalk was transmitted from the Apollo TV camera in a SSTV format of 10 frames per second at 320 lines of resolution. These SSTV signals were received by radio telescopes at Parkes Observatory, the Goldstone tracking station and Honeysuckle Creek tracking station.[3][4] The format as received on Earth was incompatible with existing NTSC, PAL and SECAM television standards, so a conversion was needed for worldwide broadcast. This live conversion was crude: Simply put, the raw unconverted SSTV signal was split into two branches, with one branch sent to an analog data tape recorder where it was recorded onto fourteen-inch reels of one-inch-wide, fourteen-track analog magnetic data tapes at 120 inches per second.[5] Each of the three tracking stations would have used approximately 15 tapes for recording telemetry during the moonwalk. The other SSTV signal branch, rather than being electronically processed and converted, was sent to a high-quality video monitor where a conventional television camera (using the NTSC broadcast standard of 525 lines resolution at 30 frames per second) merely re-photographed its screen.[6] Optical limitations of both monitor and camera significantly lowered contrast, brightness and resolution of the original SSTV video whilst also putting noise in the broadcast. The video seen on home television sets was further degraded in quality by the very long and noisy analog transmission path through which the converted signal was sent, first by satellite from the receiving ground stations to Houston, Texas and thence by microwave relay transmission to New York, from where it was broadcast live to the United States and the world.
This low quality optical conversion of the Apollo 11 moonwalk video images, made with a TV camera taking pictures of a video monitor, is what was widely recorded in real-time onto videotape and kinescope. Recordings of this conversion were not lost and have long been available to the public (along with much higher quality video from later Project Apollo missions). If the SSTV tapes were to be found, modern technology would easily allow the production of higher quality television pictures from the Apollo 11 moonwalk than have ever been seen, other than by the few technicians and others who watched the SSTV transmission on video monitors as it was received.[7] An amateur 8 mm film movie of about 15 minutes of Apollo 11 SSTV images, taken from another monitor before the conversion step, was rediscovered in 2005 and is available on DVD.[4]
News that these analog data tapes were missing broke on August 5, 2006 when the printed and online versions of The Sydney Morning Herald published a story with the title One giant blunder for mankind: how NASA lost moon pictures.[8] The missing tapes were among over 700 boxes of magnetic data tapes recorded throughout the Apollo program which have not been found.[5] On August 16, 2006 NASA announced its official search saying, "The original tapes may be at the Goddard Space Flight Center … or at another location within the NASA archiving system", "NASA engineers are hopeful that when the tapes are found they can use today's digital technology to provide a version of the moonwalk that is much better quality than what we have today."[9] NASA also had ongoing research reasons for finding these higher resolution tapes, since Project Orion was planned to carry out tasks similar to those of the original Apollo program, to "Get a team of astronauts to the moon and back safely".[10]
The Goddard Center's Data Evaluation Laboratory has the only known surviving piece of equipment which can read the missing tapes and was set to be closed in October 2006, causing some fear that, even if the tapes were later found, there would be no ready way to read and copy them.[11] However, equipment that could read the tapes was maintained.[3]
On November 1, 2006 Cosmos Magazine reported that some NASA telemetry tapes from the Apollo project era had been found in a small marine science laboratory within the main physics building at Curtin University of Technology in Perth, Western Australia. One of these tapes was sent to NASA for analysis. It carried no video but did show that if any of the tapes are ever found, data could likely be read from them.[12][13]
On July 16, 2009 NASA held a media briefing in which the agency released somewhat crisper-looking (and otherwise cleaned-up), post-conversion video from the live broadcast of the Apollo 11 moonwalk, some of which had been in storage for nearly 40 years. They meanwhile had concluded that the reels of tape with the SSTV signal were shipped from Australia to Goddard and then routinely erased and reused a few years later. Moreover, a backup copy of the tapes which had been made in Australia was also erased after Goddard received the reels. There is also documentation that two hours of the Apollo 11 moonwalk SSTV were recorded in Australia on a different tape format but likewise, these other tapes have not been found. The SSTV signal had been recorded on telemetry data tapes mostly as a backup which could be held in readiness and played back later if the real-time conversion and broadcast around the world failed. Since this real-time broadcast indeed worked and was widely recorded on both videotape and film, the backup video was not deemed important at the time.[3]
NASA stated that it did find several post-conversion copies of the video that are of higher quality than has been seen by the public. These include videotape recorded in Sydney after the conversion but before the satellite transmission around the world, videotape from CBS News archives (direct from NASA, without commentary), and kinescopes at Johnson Space Center. In 2009, NASA released some partially restored samples.[14][15][16][17] The full restoration of the footage, about three hours long, was completed in December 2009. Highlights of this fully enhanced video was shown to the public for the first time at the Australian Geographic Society Awards on 6 October 2010, where Buzz Aldrin was the guest of honor.[18]