Profile: Out of Sight
At the Pentagon's mad-science wing, Stefanie Tompkins is figuring out how to see without looking
When Stefanie Tompkins was a NASA-funded geologist at Science Applications International Corp. trying to analyze the mineral composition of moon rocks, she would have killed for a pair of glasses that let you "see" heat and ultraviolet light. Now one of her projects is a lens that allows you to do just that. In fact, most of her work can be roughly pigeonholed as an attempt to give soldiers a sixth sense.
Tompkins is a program manager at the Strategic Technology Office of the Defense Advanced Research Projects Agency. DARPA is the mad-science wing of the Defense Department, which cemented its reputation for creating technology "so crazy it just might work" by inventing the stealth fighter and the Internet. Tompkins fits right in. She’s working on ways to augment GPS, another DARPA-conceived innovation.
Despite its limitations, we’re becoming as dependent on GPS as we are on the five senses we were endowed with at birth. And no one is more dependent than DARPA’s core constituency: soldiers, who need a battery of tools to make sure their location is broadcast to themselves and everyone else who needs to know. But GPS often conks out when you need it the most—when you’re crawling around in uncharted caves in Afghanistan, for example, or deep in a rain forest. And, of course, even signals in the open can be jammed by hostile forces. So Tompkins is working on a number of wild ideas to add other means of knowing where you are, including triangulation by lightning strikes (you read that right).
Another of her ongoing projects involves a device that would extend color past the visible spectrum, both ultraviolet and the near infrared. How would it work? "Pick one portion of the spectrum," she says. "Convert an interferometer into a lens that gives you spectral wavelength information." The lens could be used to take pictures in the field, something you can’t do with today’s spectroscopy equipment. The resulting images would be shown, she says, "on a cellphone or rifle scope or UAV [unmanned aerial vehicle]."
Critics accuse DARPA of throwing good money at pie-in-the-sky boondoggles, a reputation it proudly embraces. Failure comes with the job; many of the program managers go there to solve problems that frustrated them in their pre-DARPA careers. At NASA, Tompkins’s study of the surface of the moon was often stymied by the complexity of the spectroscopic equipment (to say nothing of the fact that the object of study is 407 000 km away).
Scientists use spectrometers to "see" the unseeable regions of the spectrum—below 400 nanometers (violet) and above 700 nm (red). The devices are enormously helpful in understanding the composition of things like lunar materials. Lava rocks on the moon, for instance, absorb photons at around 1000 and 2000 nm. Spectroscopy is one of the things that actually works, and it’s great for NASA research. But today’s spectrometers are delicate, expensive, and hard to use—just the qualities you don’t want when you send something to the moon. And they certainly don’t translate well to the Defense Department’s stringent restrictions on size, weight, and complexity.
"The more work we put into the tools, the more complex they got," Tompkins says. "Using current technology, we would only keep making incremental improvements for the rest of our lives."
The pace of her life so far doesn’t suggest that kind of patience. Tompkins was born in South Korea (her brother was born in Tehran), and she’d already lived in Japan and Taiwan before she moved to Hawaii during her high school years. Her father was a career army officer, and her mother was a linguist for—"Actually, sorry, I’m not allowed to say," she interrupts herself. Her bachelor of arts from Princeton University was followed by four years in the Army and a Ph.D. in planetary geology from Brown University. In 2007, DARPA came calling.
The agency’s draconian term limits, designed to ensure that bureaucrats gather no moss, mean Tompkins will be looking for a new job in two years. But she obviously doesn’t mind bouncing around—physically or intellectually. She’s used to working at high intellectual altitudes. The bracing environment at DARPA means that even her acronym-laden PowerPoint presentations for the Army Research, Development, and Engineering Command are laced with references to Greek mythology. Explaining why multipath corrupts GPS positioning accuracy, she and a defense contractor colleague compare the signals to Echo, the nymph cursed by Hera, who says, "That tongue of yours, by which I have been tricked, shall have its power curtailed." "For navigation," that presentation advises earnestly, "we must curtail Echo’s powers as much as possible."