Dr. Joy Crisp of NASA’s Jet Propulsion Laboratory devotes her time working
to unearth answers about Mars’ geology. Tucked away in her prefab trailer
office in the middle of the JPL campus, she enables the efforts of the team
of scientists whose instruments will be onboard two rovers destined to land
on Mars in 2004. These twin robots, part of the Mars Exploration Rover
mission, will search for clues about water’s past on Mars, and attempt to
answer how the rocks and soils around their respective landing sites formed.
Crisp plays many roles in the mission, but principal among them is to
represent the interests of the science team to the engineering teams and to
report to NASA headquarters about the mission’s ability to meet its
scientific objectives. The job requires superior scientific breadth,
diplomacy and judgment.
"What I try do," Crisp said, "is to make sure that the science return of the
mission is as good as it can be."
To keep all-important channels of communication open, she keeps a glass jar
of candy sitting just by her opened office door.
"I like interacting with people. The candy jar is a good way to get people
who are passing by to pop their head in here and talk a bit about what’s
going on, while they dip their hand in to get some candy. It helps break up
the workday. Plus, if I need to talk to someone but can’t find them, usually
the candy jar will lure them in."
She works well beyond 40 hours a week, often staying in her office long past
dark. Her computer has a sticker paying tribute to the benefits of coffee. A
miniature Mars Sojourner rover sits on top of her monitor. Above her
computer hangs a framed artist’s conception of the solar system’s largest
canyon, Mars’ Valles Marineris.
Her desk is a portrait in multitasking, scattered with a wide variety of
mission and science planning paperwork. A tall bookcase is filled with
geology and other scientific books. Crisp and her husband, also a planetary
scientist working at JPL, sometimes break their routine of talking shop
during their commute and listen to books on tape.
Born and raised in Colorado Springs, Colorado, Crisp received her bachelor’s
degree in geology from Carleton College in Minnesota. When she entered
Carleton, she was not sure in which field of study she wanted to major, but
enrolled in many math courses. During her second year she wondered what she
would do with a math background. She couldn’t envision herself as a math
teacher. Almost as a last resort, she took a course in geology. She began
taking more geology courses while still pursuing math, then eventually
dropped the math emphasis and focused on geology.
Before beginning her work as a scientist at JPL, she received her master’s
degree and her Ph.D. in geology from Princeton University in 1984. After
graduation, she was appointed as a postdoctoral research scientist at the
University of California Los Angeles for more than two years. There, she
conducted experiments subjecting rocks from the Canary Islands to high
pressures and temperatures, testing the reactions of the rocks at conditions
like those experienced beneath volcanoes.
What about geology excites her? "Studying rocks and pulling out clues as to
how they were formed," she said. Crisp is also inspired by discoveries made
by other scientists. "When I learn about a scientist piecing together
geologic clues to find out how something was formed, I’ll stop and say to
myself, ‘Wow. That’s really exciting, the way they figured that out.’"
Crisp’s love of geology, particularly volcanic geology, is her driving
force. "Volcanic eruptions are fascinating phenomena, and I really enjoy
collecting rocks that were once liquid magma and trying to figure out how
they erupted and the conditions in which they formed."
How did Mars evolve? The history of water and volcanism on Mars are closely
intertwined. What is the history of water there? Was there ever life on
Mars? Those are the questions that drive Crisp and her colleagues to plow
through the challenges, long nights and unforgiving mission schedules that
characterize spacecraft explorations of Mars.
"Some of the questions about Mars that we are trying to answer are: What
were the environmental conditions like when the rocks formed? We are
especially interested in the possibility if water existed or still does
exist on Mars. Was there cold liquid water or hydrothermal fluids like those
seen at Yellowstone National Park involved? Was water only there for brief
flooding episodes? Mars has lots of volcanic rocks, which ties into my
interest in volcanoes, and these may hold clues to some of these questions."
One method used by field geologists to examine minerals is to cut open rocks
and study the fresh, unweathered surfaces inside. Both Mars Exploration
Rovers will be equipped with the compact equivalent of a geologist’s hammer
called a rock abrasion tool — a diamond-studded rock cutter that will grind
a hole approximately the size of a golf ball into a rock on Mars. This
multiple-hour-long process will provide Crisp’s team with freshly exposed
rock surfaces to study with the scientific instruments on board.
Crisp has traversed the ridges of Earth volcanoes such as Mauna Loa in
Hawaii, Mount Etna in Sicily and Mount Saint Helens in the Pacific
Northwest. Unable to personally hike the flanks of Martian volcanoes, Crisp
will experience the geology of Mars through the senses of robotic emissaries
– the Mars Exploration Rovers.
