Behind the counter of an abandoned McDonalds lie 48,000 lbs of 70mm tape... the only copy of extremely high-resolution images of the moon.

These tapes were recorded 40 years ago by Lunar Orbiter 1 to map the lunar surface to plan landing spots for Apollo 11 onward. They have never been seen by the public because at the time, they were classified as they reveal the extreme precision of our spy satellites. Instead, all we have ever seen are the grainy photo-of-a-photo images that were released to the public.

The spacecraft did not ship this film back to Earth. Instead, they developed the film on the Lunar Orbiter and then raster scanned the negatives with a 5 micron spot (200 lines/millimeter resolution) and beamed the data back to Earth using yet-to-be-patented-by-others lossless analog compression. Three ground stations on Earth (one was in Madrid) recorded the transmissions on these magnetic tapes.

Recovering the data has proven to be very difficult, requiring technological archeology. The only working version of the Ampex tape player ($300K when new) was discovered in a chicken coop and restored with the help of the original designer. There is only one person on Earth who still refurbishes these tape heads, and he is retiring this year. The skills to read this data archive are on the cusp of disappearing forever.