麻豆传媒

ALREADY a space fanatic in high school, Keri Bean was at Space Camp when she saw the IMAX documentary . Seeing how much scientists on the rover missions cared about their distant charges, Spirit and Opportunity, Bean became determined to join the endeavour.

Today, Bean is a mission operations engineer at NASA鈥檚 Jet Propulsion Laboratory (JPL) in California, training for what she sees as the world鈥檚 coolest job: driving a Mars Rover.

The Spirit and Opportunity missions were intended to last three months. Spirit went six years before giving up the ghost in 2010. Incredibly, Opportunity was going strong until June this year, when a planet-wide dust storm blocked sunlight from hitting its solar panels, putting it out of action. Only when the haze clears will Bean know if her dreams of driving Opportunity are forever dashed.

When did you last hear from Opportunity?

On 10 June, when a global dust storm covered Mars. The dust in the atmosphere has prevented Opportunity from charging her batteries. We get these dust storms every couple of Mars years, but we don鈥檛 usually lose all contact. This one is more intense. But all our modelling indicates that the rover will come back. In fact, we usually come out of dust storms with cleaner solar panels because of the wind blowing the dust off.

Travelling 45 kilometres in 14 years must make Opportunity the slowest vehicle in the solar system. How does driving it work?

We have a couple of different ways. You can send specific instructions, like 鈥渄rive straight forward 50 centimetres, turn 10 degrees to the right and then go another metre鈥�. Or you can see a rock in a picture taken the previous day by one of the rover鈥檚 cameras, set those coordinate points and tell the rover to drive towards it.

We typically plan up to three days in advance. The plan is converted into fairly simple computer code, and once every line has been checked, it gets converted into binary and sent up to the rover. We come up with the plan based on what the science team wants to achieve: take pictures of a particular rock, say, then drive for an hour to a new destination before sending the data back to Earth via the Odyssey satellite as it passes above the rover.

There鈥檚 never a good time for a rover to stop working, but this is bad timing for you personally.

It鈥檚 certainly frustrating. I had reached the point in my rover-driver training where I was sending some of the commands to Mars, with people checking my work. Now it鈥檚 going to be months before I get to do anything again. There are other training exercises I can do, and we have a rover test bed here on Earth with a replica model of Opportunity. It鈥檚 just not as cool as actually sending the plan to Mars.

What have you enjoyed most about working with Opportunity?

One of my favourite things was celebrating Opportunity鈥檚 5000th Martian day in February by getting the rover to take its first selfie using a camera on her outstretched robot arm. I was the tactical uplink lead for that day, in charge of rover planning and resources. A lot of people were sceptical because the camera was a black and white microscope that only focuses when it鈥檚 a couple of millimetres from what we are picturing. Everyone was like, 鈥淚t鈥檚 going to be blurry. Why are we even bothering?鈥�

When the images came down a few days later, clearer than we expected (see above), everyone was like, 鈥淲hy didn鈥檛 we do this before? This is amazing!鈥�

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Opportunity inspires fierce loyalty. Why?

It鈥檚 such a stressful but rewarding job that you start to see the rover as an extension of yourself. Instead of saying, 鈥渢he rover is going to move to this rock today鈥�, we say 鈥渨e鈥檙e moving to that rock today鈥�. We feel a personal connection.

We are like frantic parents. Just about every night since we lost contact I鈥檝e had a dream of me standing next to her, patting her head and wiping the dust off her camera lenses and saying, 鈥淲e鈥檙e here with you, it鈥檚 OK鈥�. I鈥檓 sure I鈥檓 not the only one at JPL thinking like that.

Is this sort of emotional attachment factored into such missions?

JPL already caters to this in unique ways. One long-standing tradition is that during critical events like, say, landing a rover on Mars, the lab provides an ice cream freezer for a few weeks. I鈥檝e even heard of funerals for missions. When I found out that Spirit 鈥� Opportunity鈥檚 twin 鈥� had died (see graphic), I went home and cried for hours. And though I wasn鈥檛 a part of the Cassini mission to Saturn, NASA brought in grief counsellors when it ended. They knew exactly when the mission was going to end, and that Cassini had had a good life, but it鈥檚 still rough.

Are your driving skills transferable to other rover missions?

Administrators for some of the other rovers have indicated they will let me drive. But I haven鈥檛 put too much thought into that yet because I want to be there for Opportunity.

This article appeared in print under the headline 鈥淟earner driver on Mars鈥�