Boldly Opening a New Window Onto Mars

Mars is looking larger in the windshield with every passing day. On Sunday evening, California time, NASA’s one-ton, S.U.V.-sized Curiosity rover should land at Gale Crater — capping a long ride from Earth and a tricky landing — and open a new, high-tech window onto remote exploration of the Red Planet.

Explorations that have preceded our Mars Science Laboratory mission have done an amazing job blazing the trail. Those pioneers went “where no rover has gone before” and discovered many new things without the benefit of knowing in advance what they might be.

But never before have we reached out to Mars with a spacecraft designed to address such a challenging objective as evaluating the prospects for future missions aimed at the search for life. NASA’s Mars Science Laboratory mission is based on the supposition that Mars was at some point in its history habitable. But we’re not looking for life itself; instead, we’re looking for habitable environments.

As chief scientist for the Mars Science Laboratory mission, I am usually so deep into mission planning that I tend to become immersed in all the arcane details of learning how to operate the rover on the surface of Mars. Imagine buying a $2.5 billion car with a 10,000-page owner’s manual; one that you don’t just have to read but you must also write, because it’s the first and only one that will ever be made.

The step forward we are about to take is remarkable. We are going to be flying in a sort of time machine, created to reconstruct what the surface of Mars looked like billions of years ago. We may get glimpses of time that go back so far that they are equivalent to the time on Earth when microbial life was first evolving. The earliest history of Mars is better preserved than it is on Earth, and so we have a chance to gain insight into the development of our own planet through studying Mars.

The essential ingredients for a habitable environment are water, energy and carbon. Past missions have determined that Mars had liquid water in its past — and occasionally has in its present. These missions also hinted at locations where natural chemical processes could have generated energy for metabolism. But where is the organic carbon that makes the metabolism of all living things possible?

That is where we fit in. Going back billions of years ago in geologic time is tough stuff, but Curiosity is well equipped to do this because of two of its most important qualities.

First, it is a laboratory complete with funnels, test tubes, magnifiers, mass spectrometers, gas analyzers, ovens, and a sampling system with a drill strong enough to chisel away concrete. Not to mention its 17 cameras, including several with color, video capture and HD resolution. Second, it is a plutonium-powered rover, allowing it to take its laboratory on the road for years on end.

This mobility feature turns out to be very important because the search for organic carbon can be an elusive game. Curiosity can scan the terrain looking for the most target-rich environment, and then drive there where its onboard laboratory can be put to the test.

Which leads me to the “there” in which Curiosity will do its geologic bidding. Gale Crater was chosen after a five-year study of possible landing sites. Within this ancient impact basin lies an equally ancient riverbed that provides records of flowing surface water and mineral-rich fractured terrains. In the middle of this 150-kilometer-wide crater rises a mountain where Curiosity will be spending most of its working life.

Dubbed Mount Sharp by the science team, the 5-kilometer-high peak is built of sedimentary layers that represent hundreds of millions if not a billion years of the early environmental history of Mars. It is this layering that our science team wants to get up close and personal with and that provides the kind of domain in which Curiosity can excel.

Beyond the science, I can think of no more majestic location to explore than Gale Crater and Mount Sharp. While early images from the rover will be low-resolution and black and white, soon we will all be able to be transported to the surface of Mars by the most beautifully resolved, highly detailed pictures ever taken on the surface of another planet.

Proust reminds us that the real voyage of discovery consists of not just seeking new landscapes but in having new eyes. The extraordinary perspective that Curiosity will provide may some day allow us to understand why a planet that initially may have not been so different from our own began its inexorable decline while ours blossomed and flourished. And in doing so it tells us something about ourselves and where our deepest roots may lie.