In July 1962, a Single Missing Hyphen in the Guidance Code of NASA's Mariner 1 Probe Sent It Veering Off Course Seconds After Launch, Forcing Range Safety Officers to Destroy a Venus Mission that Had Cost Roughly $18 Million — a Typo Arthur C. Clarke Later Called the Most Expensive in History.

In July 1962, a single missing hyphen in the guidance code of NASA's Mariner 1 probe sent it veering off course seconds after launch, forcing range safety officers to destroy a Venus mission that had cost roughly $18 million — a typo Arthur C. Clarke later called the most expensive in history.

On July 22, 1962, an Atlas-Agena rocket lifted off from Cape Canaveral carrying Mariner 1, the first American spacecraft ever built to reach another planet. It flew for just under five minutes before the range safety officer at the Cape pressed a button, and the rocket — along with the small probe bolted to its nose, bound for Venus — was torn apart above the Atlantic. The cause, once investigators dug through the guidance code, came down to a s…

In 1962, a missing overbar in Mariner 1’s guidance code helped send America’s Venus probe off course, forcing range safety to destroy an $18.5 million spacecraft in under five minutes

On the evening of July 22, 1962, an Atlas-Agena rocket lifted off Cape Canaveral carrying Mariner 1, the first spacecraft the United States had ever aimed at another planet. Two hundred and ninety-three seconds later, the Range Safety Officer at the Cape watched the rocket veer toward inhabited coastline and pressed the destruct button. The probe fell in pieces into the Atlantic. The cause, when investigators traced it back through the guidance …