In my junior year of high school, I knew that it was time to focus on a specific area of natural history. For a while, I thought about becoming a park naturalist but learned that the path to that career required a degree in a specific science. Ultimately, my decision to pursue geology was made by considering the aspects I liked most– the outdoors, rocks and minerals, geography, plants, and animals (as fossils). After finishing my Bachelor of Science degree in geology, I concentrated on paleontology with close connections to biology in graduate school. As part of my program of study, I spent a summer at a marine laboratory, studying the modern (living) forms of the fossil groups that I was researching in the rock record.

On a more complex level, in planetary science we live in a unique period of exploration. In the last quarter century, we have had the marvelous opportunity to see new worlds for the first time. Never before, and never again will there be the chance to see the primary Solar System objects as a "first! " These first views provide an enormous stimulus and create a "drive" to want to understand what we are seeing. How do those erupting volcanoes on Io, a moon of Jupiter, work? What caused the rivers on Mars to dry up? Why are the volcanoes and canyonlands on Mars so big in comparison to similar features on Earth? The list of questions is nearly endless. And each time we send a new voyage of exploration to the planets, we get more data which generate even more questions.

How are these questions answered? Few scientists work in isolation, especially in planetary science. Most missions involve teams of scientists working together to design experiments, plan observations, and analyze the data when they are returned to Earth. In the early stages, ideas are proposed, discussed, and usually rejected. Although occasionally someone may come up with a brilliant answer the first time, mostly solutions require much discussion and 'testing' before a valid answer is found. In my own case, in addition to discussions with colleagues, interactions with our students are particularly important for bringing out fresh ideas.

The creative process also involves adaptations of old ideas to new problems. For example, when the first images were returned from Mars showing sand dunes and other wind–related features, I became interested in how sand and dust might behave in the thin Martian atmosphere. The classic work on windblown sand on Earth had been written more than 30 years earlier by a British military engineer who used a wind tunnel in his studies. It seemed to me that a similar approach could be used to study wind processes on Mars, but with adaptations to the Martian environment. Although the gravity, atmosphere, and other conditions are quite different, the basic process seemed to be same. Through a team of planetary geologists, atmospheric scientists, and engineers, a wind tunnel was put into operation which enabled us to understand how sand and dust is moved by winds on Mars and provided insight into the resulting geology. This facility is still used for related experiments, as well as for testing spacecraft components and instruments in a simulated Martian environment.

Why not just complete the exploration of Mars by robots controlled from Earth? Because of the communication lag time between Earth and Mars, operating even a simple robot doing the simplest of tasks is frustratingly slow. Future technology will help with some of these problems, but there will always be limitations that can be overcome only by human presence, in which people can react to new discoveries on Mars in real time, and make decisions that cannot be made by machines.

In the early exploration of the American West, many of the expeditions were led by, or involved, geologists. These scientists had broad training in field studies and often were able to synthesize complex natural systems. It was for this reason that the first (and only!) scientist–astronaut sent to the Moon was a geologist, Harrison "Jack" Schmitt. It is likely that geologists will also be among the first humans to set foot on Mars in order to carry out extensive exploration projects. As part of early exploration, essential resources such as water and minerals needed to support Martian communities will be sought. Consequently, a high priority in the development of the communities should be the infrastructure to enable exploration activities.