"A Planetary Geologist Keeps Her Eye on the Planets"
|Prockter relaxes with some African hand drumming.
When Louise Prockter was in secondary school in North London's Winchmore Hill, she says they didn't teach things like Earth science. So when she finished school at 17, studying the surface of planets was the farthest thing from her mind. In fact, she spent a number of years working in marketing and advertising at newspapers in London before she decided to take a correspondence Science Foundation course through Britain's Open University.
"The course covered physics, chemistry, biology, and Earth science," Prockter explains. "It really grabbed my attention. I enjoyed learning about volcanoes and earthquakes and all of those natural things that go on in the Earth. I totally fell in love with it and realized I didn't want to spend my life working at my rather soulless job." Soon after taking that course, she gave up her job, sold her flat in London, and went to school full-time to study geophysics.
Even then, it wasn't until her final year in college that she took a course in planetary science. "Up until then, I never really had a clear idea of what I wanted to do," she says. "Miraculously, I ended up landing on my feet."
To be more precise, she landed in the Department of Geological Sciences at Brown University as a graduate student. With James W. Head, III, as her advisor, Prockter studied high-resolution sonar images of the Mid-Atlantic Ridge and visited the Pacific Ocean floor in the research submersible vehicle Alvin.
After analyzing a series of images of Europa taken by the Jupiter-orbiting Galileo spacecraft, Prockter discovered signs of surface folds, which are formed when the icy crust is squeezed like an accordion by gravitational forces. These folds provided additional evidence for predictions of a flexing Europan crust, which is alternately stretched and squeezed as the moon orbits Jupiter.
"I was very lucky in graduate school," Prockter notes. "My advisor gave me the opportunity to look at Galileo data that no one had seen before. I got so involved in that mission. I was interested in research, but I really wanted to work on a mission."
After graduate school, she immediately started working at the Johns Hopkins University Applied Physics Laboratory on the Near Earth Asteroid Rendezvous (NEAR) Shoemaker mission as a member of the camera team. In fact, she was one of the first people to see images of the rocky surface of the asteroid Eros as NEAR Shoemaker made its historic landing on the space rock.
As the lead instrument scientist for MESSENGER's Mercury Dual Imaging System (MDIS), Prockter is all set to train her keen eye on images of Venus, during the spacecraft's second flyby of that planet in June, and then on Mercury. "The MDIS will be among the most active instruments during the Venus 2 encounter," she says. "We will start taking images a few weeks before the flyby, and we are planning a full suite of operations 30 hours on either side of the encounter."
MESSENGER's trajectory is among the most complex ever undertaken by a spacecraft. When it's all said and done, the spacecraft will have traveled 7.9 billion kilometers, flying by Earth once, Venus twice, and Mercury three times before settling into Mercury's orbit.
"The pace of the mission can get quite hectic," Prockter says. "The spacecraft keeps moving no matter what's going on in your life, and balancing all that can be a challenge."
To keep a level head, Prockter practices yoga. She's also taken up African hand drumming, an art form she experienced years ago when she and a bunch of fellow students took a 15-day bus trip across the United States. "We rode and slept in an ancient 1950s bus," she says. "Every day, we'd stop at some place different. I got to see a lot of the country's national parks, if only briefly. One of the bus drivers had a hand drum, and every night we'd build a camp fire and he'd play it. I was inspired; I just really got into it."
She's not afraid to try new things, she says, a trait she finds common among her fellow scientists. "What we do is so obscure," she says. "We get an image of a planet's surface from a spacecraft and try to work out all the things that have happened to it over the last four billion years. The work is careful, logical, methodical, very rigorous. I think there is a part of all scientists that just wants to be playful and creative."
Her work thus far has taken her from one end of the solar system to the other. Ultimately, though, she wants to work on a Europa geophysical mission. When Galileo surveyed Europa in the late 1990s, Prockter and other scientists found that its surface was crisscrossed with fractures from mere meters to thousands of kilometers in size, and that many of these were formed of ice mixed with organic matter that probably came up from the subsurface of the moon. "It's one of the most alien landscapes I've ever seen," she says. "The surface is ice, but how far down is it frozen? How deep is the ocean we think underlies the ice shell? In many ways, Galileo raised more questions than it answered about Europa, and I would love to go back and learn more."
by Paulette Campbell, Johns Hopkins University Applied Physics Laboratory