This summer we're re-running some of our most popular articles in case you didn't see them the first time round. So, as thoughts turn to vacations, it's time to imagine holidays on the Moon and what you'd film them with...
On July 20 1969, Neil Armstrong descended the steps of the Lunar Lander and became the first man ever to walk on the surface of the moon. What few people realise though is that the grainy, ghostlike images we all associate with that event were not the best quality ones recorded and that the tapes of that original footage have all disappeared.
The whole saga is detailed at length in NASA's report on the subject, 'The Apollo 11 Telemetry Data Recordings: A Final Report', though even it acknowledges that its conclusions are only probable and not necessarily the end of the matter.
But first, we have to rewind over forty years to when humanity stood on the brink of something really rather extraordinary and NASA was on the verge of sending three men to the moon.
Ever since the inception of the Mercury programme, the Agency had been keenly aware of the importance of television in selling its story to the public and keeping its budget, and so there were detailed plans for live televised pictures from the landing. However, there wasn't exactly a lot of bandwidth for them. Voice, telemetry, biomedical data, and television all had to share the same transmission link from an antenna atop the Lunar Module, and television only got allocated 500kHz of the spectrum. Seeing that the commercial television of the time relied on having 4.5MHz at its disposal, there was therefore a bit of a problem.
The solution was to use a special camera mounted inside the door of the module developed by Baltimore's Westinghouse Electric Corporation which used a non-standard scan format of 10 frames per second and a 320 line resolution, compared with the (then) US television standard of 30 frames per second and 525 lines. And, because commercial television didn't have a hope of being able to transmit that signal, RCA was also hired in turn to build a scan converter, which was then installed in the three tracking stations around the world that were scheduled to accept the live feed, Goldstone in California, Honeysuckle Creek and Parkes in Australia (the latter being where the events of the movie The Dish are played out).
The plan was to convert the signal on site using the RCA box before it was then sent to Mission Control in Houston via a mix of microwave links, communications satellites, and analogue phone landlines depending on exactly where in the world the tracking station was. Meanwhile engineers at the tracking stations would tape the original telemetry, including the video signal, onto one-inch magnetic tapes for backup.