MIDDLEBURY, Vt. - It was one small step toward his dream of space exploration, but Cameron Mercer '11 got a taste of the real thing last summer when he interned at NASA's Marshall Space Flight Center in Huntsville, Ala[CM1] ., thanks to funding from the Vermont Space Grant Consortium. Mercer, who grew up in a family of scientists and self-described "Trekkies," was thrilled for the chance to work with NASA's Science Operations Working Group on the Mars Exploration Rover project.
His assignment may have been very different if a 2007 dust storm on Mars hadn't disabled a key instrument called the Mini Thermal Emission Spectrometer on the rover known as Opportunity. The disabled device was used to identify locally unique rocks on the Martian surface, a crucial step for efficient planning of the rovers' upcoming operations.
Mercer, a joint major in physics and geology, worked with a group whose task it was to recover the abilities of the disabled equipment by analyzing photos of the rocks sent back by the rover's Panoramic Camera (Pancam). Images from the Pancam are taken with several color filters, which are put together to form "reflectance spectra" that can tell the scientists about the physical properties of the rocks. He then analyzed the overall dataset to look for variability in the rock spectra, which could suggest an unusual rock that deserved special attention from the rover.
The main purpose of the rover project is to look for evidence of water on the Martian surface, so the ability to efficiently look at the geologic properties of the rocks is essential. Numerous clues found in this process offer the tantalizing possibility that at one time Mars had a climate and atmosphere that was hospitable to life. It's this kind of exciting potential that kept Mercer energized through reams of research data.
"By looking at the actual rocks up close and in person, you can discover things that you can't get from orbit," he says. "This can tell us things about Mars - both geologically and about its atmosphere."
Mercer says a high point of the summer was when the rover Opportunity actually discovered a new nickel-iron meteorite. As the scientists drove up to the large rock, they realized it was too big to have survived impact with the Martian surface given the planet's current atmosphere. The implication is that the atmosphere had to have been thicker at one time, indicating the possibility of more carbon dioxide and water vapor.
Barbara Cohen, a lead scientist on the Mars Rover project and Mercer's internship mentor, says Mercer was a welcome addition to the summer team. "It was great to have Cameron here to work on the science of this project and to introduce him to the Rovers and how they work," Cohen said. "He brought a fantastic perspective as a physicist, mathematician and someone who understands logic and quantitative analysis. He was always able to go off and find a logical way to attack the problem."
Cohen was not the only one to notice Mercer's scientific skills. At the end of the summer, Mercer won first place for "best science" in the annual poster session sponsored by Lockheed Martin, in which all of the interns participate. At Cohen's invitation, Mercer will be entering a refined version of his winning poster next spring at the annual Lunar and Planetary Science Conference in Houston, a major industry event that draws 3,000 participants from around the world.
Mercer has re-focused on his Middlebury work now, which includes endless hours in the science labs, drum lessons, varsity swimming and his newest passion - scuba diving. The thousand-dollar prize for his poster came in handy toward the purchase of new diving equipment. Mercer says his motivation to dive into dark, murky places is similar to his passion for space exploration. "It's all about going places people haven't gone before. My ultimate goal? I'd like to be the guy out on the moon collecting the samples and doing the field geology!"