Thursday 19 July 2012

Riding Along With the Mars Rover Drivers



How a dedicated crew sets their watches to Mars time and drives Mars rover Opportunity from 100 million miles awaypportunity Rolls On Maas Digital LLC for Cornell University and NASA/JPL via Wikimedia
Scott Maxwell stared at his bedroom ceiling in the hours after his first drive, restless with excitement. All systems were go, and he'd sent the commands by the time he left the Jet Propulsion Laboratory. Now he was supposed to sleep before his next shift on Mars time. But he knew that on the fourth planet from the sun, the Spirit rover’s wheels had started to move.
“I was thinking that at that moment, there is a robot on another planet, doing what I told it to do. I could not imagine going to sleep,” Maxwell recalls. “It just blew my mind. And I still think it’s amazing that what I do with my day job is reach out my hand across 100 million miles across of empty space, and move something on another planet.”
Maxwell is one member of a team of engineers and scientists who have spent nearly a decade working with NASA’s intrepid Mars Exploration Rovers, Spirit and Opportunity, maneuvering them across windblown Martian terrain and into groundbreaking new discoveries. Many of them, along with a new cadre of researchers, will also command the new Mars rover Curiosity, set to land in three weeks. That rover is far more complex and more powerful, and designed to last much longer than the twin rovers’ initial three-month lifespan. But the MER mission, as it’s known, set the stage in many ways — including how to live and work as a Mars rover driver.

The humans do their work in a fairly unremarkable setting, wearing normal clothes perched at normal computers, holding conference calls inside normal cubicles in southern California. Yet they’re driving little cars on Mars, an incredible feat that never ceases to amaze team members like Maxwell. It is not easy, neither on the team members’ own health — living on Mars time is hell for some — nor on their personal relationships. But ask them, and they’ll say it’s been the trip of a lifetime.
Waking up to drive a rover on Mars is complex from the moment you hit the snooze button. In the early days of a mission, engineers live according to the Martian clock. A Martian day, called a sol, is about 40 minutes longer than an Earth day, so engineers show up for their shifts 40 Earth-minutes later each day. Mars timekeeping requires some detailed calculations. From the perspective of a rover driver, it’s awful — unless you’re Maxwell, who claims to love itDriving the Rover: Scott Maxwell at his workstation, connected to Mars.  Courtesy NASA

Morning people like Deborah Bass, a scientist at JPL who worked on MER and the Phoenix lander, and Ray Arvidson, the mission’s deputy principal investigator, describe Mars time less than fondly. “Oh, it hurts,” Arvidson says. “It’s like coming back from a trip to Europe every day.” Nowadays, the MER team plans ahead so they can work normal Earth schedules, but 300 to 400 people will revert to Mars time and its bizarre timelines after Curiosity lands.
Spirit and Opportunity are solar-powered, so they have to work during the Martian day to ensure they have enough juice. Though Curiosity has a nuclear generator, it, too, will work mostly during the day so its cameras and instruments can see. That means planning is key, according to Bass.
“We want to be ready so as soon as that little spacecraft wakes up on Mars, we have a whole set of stuff for it to do,” she says. “We send it at like 5 in the morning on Mars, and that’s the start of the day. So we say we work the Martian night shift.”
Thanks to Mars time, this makes for some long days and nights, and managers at the Jet Propulsion Laboratory have to make sure people go home to bed. “It is so compelling, it can be challenging to shut it off and go home,” Bass acknowledges.
It’s also challenging because team members feel real affection for the rovers and each other, and want to be there for every new step. The mission has served as a bedrock for people who have worked together for more than a decade, surviving deaths in their families, divorces and other traumatic experiences. Initially, engineers and scientists were tied to one rover or the other, and came to know them closely, discussing Spirit and "Oppy's" personalities the way the rest of us might discuss our pets.
“They are personalities we imbue them with, but they’re not less real for that. If you ever had a first car, and you loved that car — maybe it was cantankerous, maybe it was great that car is somebody to you. This is like that, on steroids,” Maxwell says. “To the extent that you can say this about the rovers that it has a personality and is ‘somebody’  the character that she is, is the product of the whole team that is operating her.”

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