"EUL?" "Go"

"SOWG chair?" "Go"

"I am the TUL, I am Go"

"Mission Manager?" "Go."

The familiar cadence of call and response causes a rise of expectancy and excitement even as I hear it for the 365th time. Another plan for another day, declared ready for radiation to Mars.

On 5 August of last year, we were captivated for a brief moment as Nasa's Jet Propulsion Laboratory tried to land a 1-ton Mini Cooper-sized rover on Mars using a seemingly crazy combination of parachutes, rockets, and a sky crane. And wildly succeeded as the world watched.

As a member of the science team, I paced in the back of our JPL room that night, gripping a piece of paper that became progressively more wrinkled as I listened to the landing team chatter, checking that all was going by the checklist. High fives, fist pumps, hugs, and not a few tears erupted as we heard "Curiosity is safe on Mars". Watching the inspiring video "Where were you when Curiosity landed?" brings me back to that moment.

Where were you? Millions tuned in to check out the first pictures. In what has become typical for rover missions, the only thing that crashed that night were a few of Nasa's websites, which slowed to a crawl as people, excited and curious about what this mission might bring, wanted to see the first photos from this new spot on another planet.

For the last year, the Mars Science Laboratory, aptly named Curiosity, has been traversing the surface of Gale Crater, poking and prodding rocks and soils and sniffing the atmosphere with each of the sophisticated science and sampling instruments we armed it with. Guided by a team of hundreds here on Earth, the six wheeled adventurer has trekked a kilometer, drilled holes in the ground, and revealed that this part of Mars, about 3bn years ago, had a small lake that could have supported life, a possible habitat.



A habitat is a rare and precious thing in this universe. Earth's closest twin, Venus, hosts a 870F (465.6C) sulfurous atmosphere. No habitat there. Of the 900+ exoplanets, discovered orbiting other stars outside our solar system, most are too large, too hot, too cold or not quite right for life as we know it. Mars, though, gets more interesting the closer we look.

Since 2000, Nasa's concerted program of exploration sent two orbiters, a lander, and three rovers (including Opportunity, still trekking after 10 years). The European Space Agency joined in with an orbiter. Probing the depths of time using the rock record reveals Mars' environments of the past. During the same geological instant the first microbes were preserved in Earth's fossil record, Mars had lakes, rivers, hydrothermal systems, and soils in different spots across the planet. "Water on Mars" may have been the most overused space exploration headline of the decade, but it called attention to a richly diverse, potentially habitable world, in the past much more like our own.

But that is not Mars today. Now Mars is a planet on the edge where water, if it exists, is there only ephemerally. Why did this planet's history diverge so starkly from our own? What happened? Why does Curiosity open its camera eyes each morning to a cold, dry, dusty, rusted world, while our own planet hangs as a beautiful orb with swirling clouds, oceans teeming with life, and a flush of green vegetation covering the surface.

This is why I explore. It's curiosity that drives me as I help drive Curiosity.



Exploration is not without cost. Over 10 years – conception, build, launch, landing and continuing operation – Curiosity spent about $2.5bn here on Earth. That's a lot. But it's also the cost of one movie ticket for each person in the United States during the past decade. (It's a pretty darn good movie, worth seeing, in my opinion).

Exploration is a driver of innovation, now as in the days of the first seafaring navigators. There remain great challenges of exploration to be undertaken. In trying to do things that are hard, we learn something about ourselves. We explore the limits of our technology and then push beyond. Space is the 21st century frontier.

Nasa's next goals are to send a small orbiter and lander to Mars to measure the atmosphere and collect seismic data, a small mission to study the thin exosphere of the moon and a spacecraft to collect samples from an asteroid. But it will require a public push, a vote for curiosity, if we want to be bolder: for Nasa's next rover to Mars to have the samples it collects sent back to Earth, to travel to Jupiter's icy moon Europa and explore its ocean, to splash down in the methane lakes of Saturn's moon Titan.



We should be bold. It is human nature to look outward with wonder and curiosity. Take a small portion of resources and set them aside to do something hard that pushes boundaries in new ways. On Mars, Curiosity's boundary-pushing journey is just beginning. In the next year, we have a 10K trek then start a 3,000 ft climb, an endurance challenge to travel the record of Mars history preserved in the rock layers of Gale Crater's Mount Sharp. Each Mars morning Curiosity beeps and warms to life, ready for exploration.