Answer: Watches

Mars has a lot of similarities to Earth when it comes to the passage of time: the red planet has a similar axial tilt, a similar rotation period, and it experiences seasonal changes like Earth (albeit minus spring flowers and Christmas caroling, of course).

Despite the similarity between an Earth day and a Martian day, however, it posed a significant challenge to the NASA scientists who worked with the rovers, Spirit and Opportunity, day in and day out. Because of the temperature swings on Mars and, more importantly, the rovers’ dependence on solar power, the mission was beholden to the rhythm of the Martian day. The Martian day is 39 minutes longer than an Earth day, which means the work day for the NASA scientists directly responsible for the day to day operations of the rovers drifted out of sync with Earth time by 39 minutes every day.

To help the rover drivers and other support staff cope with the time differences and keep the rovers on schedule, NASA commissioned special watches for the team. At first, they looked into getting a custom quartz-crystal driven watch made, but they found it would take a minimum order of 10,000 watches—and they definitely didn’t have 10,000 people who needed the watch. When they looked into mechanical watches, watchmaker after watchmaker told them that they didn’t want to take on the project. Finally, they came across Garo Anserlian, a master watchmaker who was willing to invest the effort into the project.

Through trial, error, and determination, Anserlian came up with a work flow for adjusting and modifying mechanical watches to precisely lose 39 minutes a day in order to drift out of the familiar pattern of Earth days and into Martian days. The watches were a success and worn by many of the scientists working on the Mars Exploration Rover project. Anserlian described seeing his watches during broadcasts of the mission as such: “I felt proud; I got goosebumps. I saw that some of them had two watches on and I thought, one of them was mine! I was proud as an American that it landed and secondly that my watches will be used.”

And proud he should be, as his willingness to take on a challenge in pursuit of the greater good is a fundamental underpinning of space exploration and humankind’s quest to reach out into the far reaches of our solar system and beyond.