Epic bugs: the curious case of the first sailor

Mariner 1

Next time when you come across a job ad with a title “Full time Range Safety Officer”, do have a read as it could be of interest to you. Over here in the UK, most people would associate a “range” with a  “large cooking stove with burners or hotplates and one or more ovens, all of which are kept continually hot”. This job is nothing to do with that, you will not be employed by a retirement home to make sure that the old dears don’t burn themselves on the cooker.

Instead, you will be one of the most destructive forces in nature, using the minimum of your muscle energy to destroy hundreds of millions of dollars of the most advanced devices the world has ever seen in a matter of fractions of a second. Yeah baby.

Easily googleable history hasn’t recorded who was the NASA’s person in charge of the safety of personnel and assets (the said “range safety officer”) that in 1962 pressed the button that started the self-destruction of Mariner 1 spacecraft. Nor do we know how he or she felt about it. As a proud employee of the NASA’s esteemed Jet Propulsion Laboratory, a committed team player, he or she would have experienced utmost levels of stress that sent him or her into a prolonged depression. Alternatively, as an average human being, it may just have (secretly) been a “yes!” or “who’s the daddy?” moment. We’ll never know.

So what happened to Mariner 1?  It malfunctioned and it was destroyed. But did it malfunction?

The Spacecraft

The main mission of Mariner 1 was to fly by Venus and collect important scientific data. It didn’t have a camera but what it had was cutting edge science and tech.  The project cost $18.6million, close to $150million in today’s money. It would have been the first interplanetary aircraft, the first human contraption to reach other planets.

Mariner’s rocket, known as Atlas-Agena, had associated two radar systems that were supposed to monitor her speed and distance and relay that data back to ground computers for analysis and advice on the trajectory of the rocket, making sure it was on the right path.

Having two radars feeding data involved certain level of synchronisation as there was a small time difference between the signals coming from the radars (43 ms to be precise) . The formula that was applied to compensate for this tiny time delay included maths that involved an operation which had two variations: the basic one represented with symbol “R” and a slightly different noted as “R with Overbar” R with overbar. The difference was that the version with the overbar was grouping some values together and as such was outputting somewhat different results to ordinary “R”.

The Launch

Here comes the plot: when the formula was inputted into the computer, the poor soul that was typing it omitted  to enter the “overbar” variation an instead put in plain “R”.

So now, on 22 July 1962, the Marner 1 on Atlas-Agena is launched and is happily climbing through the atmosphere sticking religiously to its prescribed trajectory. The monitoring radars are doing their job and sending the correct information to the ground control but the computers processing the data, WITHOUT THE OVERBAR, are concluding that the rocket is slightly off the trajectory and are sending signals for correction.

As you would imagine this leads to trouble, and due to false corrections, the rocket gets increasingly pulled away from its trajectory. Finally, 293 seconds into the launch, our hero from the beginning of this story, the Range Safety Officer, decides that he must act to protect the world at large from a stray rocket, presses the (presumably) red button and watches on the TV screens the most expensive firework NASA has ever financed.

The Epilogue

And that is the sad story of the luckless sailor, the Mariner 1. Ironically, the “overbar” fiasco was intentionally wrongly reported by the popular press as the “hyphen” fiasco, on the basis that no-one would know  what an overbar is whereas everyone knows what a hyphen is. Even the great Arthur C. Clarke called it "the most expensive hyphen in history". Et tu Brute.

There is a happy-ending however. As it was the time of plenty for aerospace research, NASA pulled up their socks and in less than 5 weeks, launched the “lady in waiting”, the Mariner 2 spacecraft, that successfully accomplished Mariner 1’s mission. Although it is no longer communicating with us, it  is still out there somewhere, orbiting the Sun and enjoying its retirement with no range safety officer insight.

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