Only twelve men have walked on the moon, and it's pretty incredible how little those men used their status as Apollo astronauts to shill for products or endorsement deals. In fact, it seems like only one moon-astronaut was ever used to sell cars, and the car sold just might be the last one you'd expect.

The astronaut was the amazing Buzz Aldrin, and the car was, believe it or not, a VW Beetle. Well, I guess actually he was specifically endorsing Volkswagen's pioneering but largely ignored , released in 1972. Considering all those early astronauts were , this is a very surprising choice.

It's not surprising VW sought out Buzz Aldrin to act as spokesperson for the system. In fact, based on the ads of the time, it seems like they actually contacted him for some real evaluation and input on the system, since Aldrin was one of the few people in the world at the time to actually have had a lot of experience dealing with a vehicular computer analysis system that helped detect faults.

The ads suggest his actual input was pretty economical, word-wise:

Earlier this year, Volkswagen felt it had something advanced enough to show, not only to a man who walked on the Moon, but also to a man who was intimately familiar with the subject of computerized check-out and testing.

After a series of meetings and after seeing the system in operation and learning of plans to bring in the computers starting later this year, Colonel Aldrin's response, very simply, was: "I'm impressed."

And here's the thing: that system was pretty damn impressive, especially for the time. Remember, the very first microprocessor, the Intel 4004, only appeared one year earlier, in 1971, and the best chance most people would have of actually touching and interacting with an actual computer likely wouldn't come until three years later, when Atari introduced Pong. Nobody was doing anything like this, on this scale, in 1972.

The fact it was on a Volkswagen Beetle — a car designed in the 1930s that was already very outdated by 1972 — is even more incredible. Sure, the system was used across the VW lineup, which did include more advanced vehicles like the Type III (first with computerized fuel injection, for example) most of the cars with were normal old Beetles.

The system itself was pretty clever, if, frankly, not all that useful, really. In addition to the bulky port mounted on the firewall and the bunch of sensors wired throughout the car, the system included fridge-sized rack housing the diagnostic computer and integrated printer (at the dealer, not in the car, of course) to give the owner a full report.

Some of the sensors were just a little silly — the taillights, for example, had sensors, just in case you didn't want to rotate your eyeballs 1/16" to see if the lights were on. Later timing sensors would be added, along with the expected battery/generator/alternator voltage, tach, temperature, and so on.

There was a means for the computer to remotely start the car as well from the jack, and that led to what I think is the most clever hack of the whole thing — the system could roughly measure cylinder compression with the starter motor.

Essentially, it would crank the starter, then check the current draw of the starter motor during the engine's compression cycle for each given cylinder. The more the starter had to work, the more current it drew, and the better the compression of the cylinder. The results weren't as accurate as a real compression gauge, but it would give you a decent general idea of what the was going on (like, if one cylinder had a burned valve or something). That part is pretty clever.

The main computer unit looks like it used tubes for its display, and I'm quite sure those flashing numbers and that printer clacking out data would have impressed the crap out of your average 1972 Beetle owner.

Unfortunately, that's about all it was really good for, since most technicians could get the same basic results with methods and tools they'd been using for years and were far more comfortable with. The units were expensive and pretty ungainly, and the system didn't even last outside of the 1970s. Still, it was, in many ways, the precursor to the OBD II systems we all know and love today, and is worthy of remembering just for that.

I've seen a lot of Beetles, but I've never seen one with a fully intact Diagnostic Socket connector. I yanked the remaining bits of mine out when I in it, and even before that the socket never did anything as long as I had the car.

I sort of wish I still had it wired up — hacking a cable to connect it to a Rasberry Pi or something like that would be very cool, even if only to get access to the remote start capability so I could start my Bug with a Tweet or text message. Though, since I usually leave it in gear out of habit, that would probably just end up with me launching it onto a sidewalk or into the back of another car.

Commenter RacerEx showed me that Buzz' Lunar-roommate and first man on the moon Neil Armstrong , too. Thanks!