NASA’s Mars program has for many years been the crown jewel in its rich and ever impressive array of space exploration campaigns. The successful Sky Crane landing of the Curiosity rover in 2012 sent a tidal wave of patriotic pride across the U.S., just as Spirit and Opportunity did when they reached the Martian surface in 2004, encased in otherworldly airbag shields.
Many might assume that landing the rovers would be the hardest part of an entire mission, and indeed, from a technical vantage, a successful touchdown on Mars is incredibly difficult to pull off. But in many ways, the operation of the rovers once they’re safe on Mars is the most grueling aspect for scientists. The reason for this can be distilled into two words: Mars time.
The length of an Earth day, we decided long ago, was to be 24 hours. This 24 hours is the amount of time it takes for the Earth to complete a single revolution about its axis. Mars, though, doesn’t spin at quite the same rate—it’s a tad slower. As it turns out, one day on Mars—a sol, in NASA parlance—lasts roughly 24 hours 40 minutes.
For the earthbound scientists who planned Spirit and Opportunity’s daily activities, this minor time gap demanded major sacrifice. In order to stay in sync with the solar-powered rovers—i.e., to keep human workdays on Earth aligned with rover “workdays” on Mars—key personnel at Pasadena, California’s Jet Propulsion Laboratory (JPL), from which the rovers were being commanded, committed themselves to living on “Mars time.” Every day for the crucial three months or so of the primary mission, their workday would shift 40 minutes. Bedtime would be 40 minutes later than the day before, and they would rise 40 minutes later the next “morning.”
Very quickly, as the hosts of the first episode of the Smithsonian’s National Air and Space Museum’s new podcast tell us, living on Mars time made scientists’ schedules highly unorthodox. “It really is kind of surreal when you’re coming out at the end of the day and it’s like 5 in the morning,” says Air and Space curator Matthew Shindell, who was at JPL during the Spirit and Opportunity operations shadowing certain members of the rover teams for a graduate research project. “You feel like you should be eating dinner, but everyone else isn’t even up for breakfast yet.”
Shindell characterizes the sensation of living on Mars time as that of “constantly having jetlag.” “Your thought process isn’t as clear as it normally would be,” he says, “because you’re so often tired and not quite sure what time it’s supposed to be.”
Given everyone’s perpetually wired condition, the rover teams realized they would have to band together in order to succeed. It would only be with camaraderie, and a willingness to lend a hand to peers who weren’t feeling so hot on a particular sol, that they would be able to win the day. Despite the stressful situation, Shindell says, team members consistently treated each other with positivity.
NASA, too, was accommodating in its arrangements. For the duration of the Martian madness, Spirit and Opportunity scientists were offered housing in retrofitted apartments, whose pitch-black curtains could render the sleeping quarters dark at any time of day. And in the JPL offices where the rover programming took place, there were no windows whatsoever—scientists were free to keep their eyes on the prize, imagining themselves on Martian time with no outside light creeping in to throw them off.
Locals in town also developed a supportive fondness for the so-called “Martians,” whom they would spy at all-day diners, eating steak at breakfast time or demanding eggs at 10 PM at night.
Some of the most mission-critical personnel, Shindell says, didn’t bother with the apartments at all, and instead bounced back and forth between the Spirit and Opportunity floors of the office (which operated a day out of phase, since the rovers were on opposite sides of Mars) till exhausted, at which point they’d recuperate on cramped cots at their work stations.
Martian time took a toll on everyone with a role to play in deciding on the rovers’ daily activities—particularly those with extenuating personal concerns. “The most difficult aspect is if you have a family,” Shindell says. “You really quickly either go out of sync with your family and spend whole days where you’re on the opposite schedule, or you allow that family to pull you out of the Mars day-night cycle, so you’re never fully in sync with the work that you’re doing.”
Navigating such circumstances could be brutal. “You either suffer at work or you suffer at home,” Shindell says. “That’s one of the biggest problems that people ran into: How do I remain the father or the mother to the kids that I love while at the same time fulfilling my dream of exploring Mars?” Each member of the mission team had their own struggles.
In the end, despite all of the associated unpleasantness, Martian time worked. The mission-critical first months of Spirt and Opportunity went off more or less without a hitch—almost every day, the rovers were returning fascinating new findings. Curiosity, also managed on Mars time, followed in their footsteps with similar success. All three rovers are still active to this day, though mercifully the scientists’ schedules are much more conventional now that the primary mission directives have been accomplished.
How were these men and women able to overcome chronic fatigue and unrelenting time pressure to do a quality job day in and day out? Shindell says that, in the final analysis, it was naked resolve that won the day. The individuals in those offices had been dreaming about Mars exploration for years, if not decades, and there was no way they were about to let a little drowsiness deprive them of that dream. “It comes down to their dedication,” Shindell says. “They were living on these schedules, and everyone was sleep-deprived. But when it came down to it, at every important moment, I think they brought 100 percent.”
Future episodes of the podcast “AirSpace” will explore “astro-gastronomy,” or dining in space; how artists reimagine the realm beyond the telescope; and training for a deep space mission in a submarine. Subscriptions can be found through Apple Podcasts and other podcast platforms, or listen online.