Another inexhaustible warhorse for conspiracy theorists is the famous and controversial affair of the "lost original tapes", allegedly erased by NASA. When, in 2006, the American space agency publicly admitted, after a long and frantic search, that it could not locate the magnetic tapes containing the raw telemetry of Apollo 11's first moonwalk, the deniers cried victory! According to their twisted logic, the destruction (because that is what it was, in their eyes) of these tapes was the definitive, blatant proof of a cover-up: NASA supposedly made the "original" evidence disappear to stop modern digital analysis experts from exposing the flaws of the fake TV set! 

The historic "First Step" of Apollo 11 Commander Neil Armstrong in the Sea of Tranquility, July 20, 1969. Photo courtesy of NASA.

As always, this sensationalist deduction feeds on complete ignorance of the archaic data archiving procedures of the 1970s and of the very nature of space radio transmissions. To understand exactly what was lost, we need to take a step back and look at how the historic black-and-white images traveled from the surface of the Moon to the TV sets The small, ingeniously designed black-and-white camera that filmed Neil Armstrong climbing down the ladder during the first historic moonwalk. Photo courtesy of NASA.of half the world. The special Westinghouse camera, which Neil Armstrong deployed from a side compartment of the Lunar Module, by pulling a handle on the LM's porch before climbing down the ladder, did not transmit a standard television signal. Because of the extremely narrow bandwidth available for interplanetary radio communications, which absolutely had to give priority to the vital telemetry data (such as the astronauts' heartbeats, the oxygen levels in their suits and the status of the onboard systems), the video signal was transmitted in a proprietary analog format called SSTV (Slow-Scan Television). This format sent a meager 10 frames per second at 320 lines of resolution, compared with the 25 or 30 frames per second of normal television at the time. When this very weak raw signal reached the giant receiving antennas on Earth, in particular those at Goldstone in California and at Parkes and Honeysuckle Creek in Australia, it was immediately split into two separate streams. The first stream was recorded "as it was" on huge, very wide reels of telemetry magnetic tape, along with the spacecraft's biomedical and engineering data. The second stream, so that it could be broadcast live worldwide, had to be converted on the spot into the standard NTSC and PAL formats. The process was as ingenious as it was crude: the original SSTV video was displayed on a very high-persistence phosphor monitor and a conventional television camera, literally pointed at that screen, filmed it live, converting it and sending it to Houston for distribution to the global broadcasting networks. At the time it was the best possible solution to avoid latency or unnecessary, and noisy, signal reconversions. The infamous tapes lost by NASA are not at all "the only footage of the Moon landing", but only those specific telemetry reels containing the raw SSTV signal before that optical conversion! In the 1970s and '80s, after the golden age of space exploration, the agency suffered drastic and crippling budget cuts and faced a chronic shortage of very expensive magnetic media. The ground stations and the national archives of the Goddard Space Flight Center, literally swamped by tens of thousands of reels coming not only from the Apollo program, but from dozens of weather satellites and orbiting probes, adopted a ruthless standard recycling procedure ... Once the essential scientific data had been printed out or extracted for analysis, the telemetry tapes were routinely degaussed (wiped) and reused to record the new Skylab and Space Shuttle missions. It was a very painful and irreparable archival blunder, not a dark government conspiracy! The reels with the raw telemetry of Armstrong and Aldrin's moonwalk most likely ended up in one of these blind erasure cycles, victims of relentless bureaucracy and of the complete lack of historical foresight of the warehouse staff and administrators of the time.

One of NASA's historic magnetic tape recorders, used during the Apollo program to store telemetry data from the Apollo Command and Service Module and the Lunar Module. Photo courtesy of NASA.

But claiming that erasing these magnetic tapes means the footage of the Moon landing was destroyed is a colossal lie told in bad faith! The worldwide live broadcast, that is, the optically converted signal that was sent from Houston to every network on the planet (CBS, BBC, RAI and so on), was recorded simultaneously by dozens of independent broadcasters and is perfectly preserved in countless international historical archives. And that's not all: NASA jealously preserves all the very high-resolution still photos taken by the astronauts with the prestigious Hasselblad cameras on 70 millimeter film and still has, intact, the extremely sharp 16 millimeter color films shot by the automatic movie camera mounted in the window of the Lunar Module "Eagle", which framed the scene from above. Even more devastating for the denialist scaffolding, the agency holds and makes available to the public the original telemetry tapes and the superb high-definition color television footage of all the subsequent Apollo missions (from 12 to 17). If NASA had really wanted to destroy the evidence of a fake set, it would have incinerated all the material from every mission, starting with the detailed high-resolution films that, examined today, would easily have revealed the supposed steel wires, the zippers of the fake suits or the papier-mâché backdrops. It would certainly not have merely "lost", through a bureaucratic error, the darkest, grainiest and most blurred telemetry track of the entire program (Apollo 11's, because that is what it was), while religiously preserving dozens of hours of crystal-clear footage from the later missions aboard the Lunar Rover. Once again, the plain, banal reality of human administrative inefficiency perfectly explains a historical fact that conspiracy theorists, obsessed with the idea of an all-powerful, infallible government organization, prefer to shroud in pointless, ridiculous mystery.