“Curiosity Rover Lands Safely on Mars.” This was headline news on the day I went to meet Jane Luu, defense systems engineer and award-winning planetary astronomer. Early in her career, Luu scoped the cosmos, studying the dark void beyond Neptune. With her Ph.D. adviser David Jewitt, she discovered the Kuiper belt, vastly increasing the number of known objects in the solar system. At the same time, her research helped reduce the number of planets in our solar system to eight. Yes, she shares responsibility for the demotion of Pluto.

Scoping the dark void

When Luu arrived at the Massachusetts Institute of Technology (MIT) in Cambridge as a graduate student, her assigned adviser, Jewitt, was considering a simple question: Why is the outer solar system so empty?

In 1951, astronomer Gerard Kuiper famously predicted that debris from the formation of the solar system—Kuiper belt objects, or KBOs—should have populated the space beyond the planetary orbits. But he also said that any remnants from the event, which took place about 4.5 billion years ago, should be long gone. Jewitt calls it an antiprediction: Kuiper is famous for predicting that the objects eventually named for him didn't exist. In any case, in 1986 the conventional wisdom was that there was nothing out there.

For her main Ph.D. project at MIT, Luu dutifully and productively investigated links between two classes of celestial objects: asteroids and comets. But she made her mark proving Kuiper wrong about KBOs. If the Kuiper belt existed at all, KBOs would be dim and distant, which could explain why no one had seen them—and also make detecting them hard. Undaunted, Luu and her adviser began a years-long, systematic survey of the realms beyond Neptune. “There was a joy in challenging conventional wisdom,” Luu says.

Earlier this year, Jewitt and Luu were named co-recipients of the 2012 Kavli Prize in astrophysics for detecting the first KBO 6 years after their search began. Since then, astronomers have found thousands. Jewitt and Luu shared the award with Michael Brown, whose discovery of Eris, the largest known KBO, was the final nail in Pluto's planetary coffin. Jewitt and Luu also shared the Shaw Prize in astronomy, dubbed the “Nobel of the East.” Each award carries a cash prize of $1 million, which the recipients share. Luu plans to use her portion to pay off her mortgage, save for her daughter’s college education, and “boring things like that,” she says.

Neither award requires that the money be spent on research. That's good for Luu because she no longer does research in astronomy or astrophysics. For a decade now, Luu hasn’t viewed the night skies—at least not through a powerful telescope. Since 2001, she has been on the technical staff of MIT’s Lincoln Laboratory in Lexington, working as an engineer on defense-industry projects. Well into her second career at age 49, she is considering returning to the field where she is already something of a legend.

Immigrants, hungry for success

Luu, who is Vietnamese-American, was not to the observatory born. “As a child I had little science education," she says. "I did not grow up building telescopes like Dave [Jewitt] did growing up in England. I did not even look through a telescope until I got to graduate school.” In 1975, when she was 12, her family fled Saigon in an American military plane. Before settling in Southern California, the family of six stayed in a refugee camp, cheap motels, and, briefly, someone’s garage. “We discovered American fast food early. Our hosts didn’t feed us nearly enough,” she recalls.

Academically, she suffered no setback. Already fluent in French, she picked up English in one summer, entered the American school system with a French-English dictionary in hand, and excelled in science subjects. Her grades paved the way to a scholarship to Stanford University. She became a naturalized American citizen in 1986.

That same year, after graduating from Stanford, she worked at the Jet Propulsion Laboratory in Pasadena, California, home base for the Voyager missions. Fascinated by close-up pictures of planets, she decided to pursue astronomy.

Another Kuiper legacy

In graduate school at MIT, the search for KBOs became an obsession for Luu and her adviser. “We begged, borrowed, or stole time to keep looking, though people thought we were crazy," she says. In 1988, Jewitt left MIT and moved to the Institute for Astronomy at the University of Hawaii, Manoa. His new position gave him—and Luu—access to the telescopes at Mauna Kea. Situated above star-obstructing cloud cover, the observatory might not have existed were it not for the efforts of one Gerard Kuiper.

In the 1960s, in a bid to boost the economy after a tsunami hit the Big Island, a Hawaii Chamber of Commerce representative wrote to astronomers in Japan and the United States asking them to evaluate Hawaii’s highest mountain as a potential site for astronomical observation. Kuiper, who while visiting Maui had noticed the towering peak on the island across the channel, was the only astronomer to respond. He visited the site and persuaded the local authorities to build an access road to the peak. He did some tests and submitted a proposal to NASA to set up a telescope on Mauna Kea. Kuiper didn't get the grant, but an observatory was built on Mauna Kea. That observatory later gave Luu and Jewitt the vantage point they needed to locate Kuiper's nonexistent objects.

Working at home and abroad

Luu defended her thesis in 1990, having not yet detected any KBOs. In 1991, she won the Annie J. Cannon Award in Astronomy, given to women who have made distinguished contributions to the field. By then, she was a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics in Cambridge. “It was a shock to be back on the fast-paced East Coast after two years in Hawaii, and I found every excuse to return to the islands,” she noted in her Kavli Prize address.

On 30 August 1992, using the University of Hawaii's 2.2-meter telescope at Mauna Kea, Jewitt and Luu spotted their first KBO, initiating an intense period of discovery. They and other scientists began mapping the structure of the doughnut-shaped Kuiper belt.


CREDIT: Leaf Liang
Jane Luu's T-shirt reads: "It's okay, Pluto. I'm not a Planet either."

Luu’s achievement did not go unnoticed. Two years later, she accepted an assistant professorship at Harvard University. Harvard's hiring policies have changed, but at that time it was rare for assistant professors to win tenure. Sensing that she wasn't on track, she left Harvard after 4 years to take a tenured position at Leiden University in the Netherlands, the institution where Kuiper studied astronomy. At Leiden, she won awards for her teaching, but she says doing astronomy research in Europe was more challenging than in the United States. “Getting time on large telescopes is always hard, and a lot of it is political. But [in Europe], much of it was also driven by national interest: What does Holland get out of this collaboration, how much telescope time does France get, and so on.” Getting things done in such circumstances, Luu says, requires patience and political skill. She says she had neither.

In the Netherlands, Luu met and married Dutch astronomer Ronnie Hoogerwerf. “But I missed my life in America and wanted to be closer to friends and family.”

Homecoming

“Perhaps I had become too demoralized,” Luu says. Upon returning to the United States, “I simply didn't want to go through the tenure process again.” Nor were tenure-track positions easy to come by for planetary astronomers. “Many classical astronomers think that the solar system is too close to be part of astronomy, while many planetary scientists are interested only in parts of the solar system close enough to be easily reached with spacecraft," Jewitt explains. "So, planetary astronomers tend to get little support or recognition from either community.”

Lincoln Lab was a good prospect for an out-of-work planetary astronomer because the army monitors the skies. Luu started with the surveillance division, gravitated to engineering projects, and now builds laser-based radar systems. She likes working in a discipline—engineering—with a larger community than astronomy, but her love for her old discipline remains.

This year's biggest awards for astronomy—the Kavli and Shaw prizes—were for the discovery of the Kuiper belt, so maybe mindsets toward planetary astronomy are changing. Maybe an opportunity will open up for an astronomer who just won two of the field's most important awards.


CREDIT: Scanpix
The Kavli Prize laureates in astrophysics. Left to right: David C. Jewitt, Jane X. Luu, and Michael E. Brown.

But her return to astronomy is by no means imminent. Academia is conservative, she says, favoring those who have stuck to a predictable path; how likely is it that they would hire an engineer—even one who has won the most important astronomy awards—for a tenured astronomy faculty post? Besides, she is now the mother of a young child and she refuses to uproot her family without good reason. She is very clear about this. The co-discoverer of the Kuiper belt would like to get back to science, but she wonders, “Can I do it? I don't know.”

New horizons

The February 1996 issue of Astronomy included a profile titled "The Remarkable Odyssey of Jane Luu". Noted science writer Marcia Bartusiak wrote about Luu’s rise from refugee to Ivy League professor. In the article, Luu notes that her success might not have been possible in any other country. “I have only lived in three countries—too small a sample to come to any conclusion really,” she jokes now. She is no longer a starry-eyed astronomer but an experienced—perhaps slightly jaded—engineer. Yet there may be some interesting twists remaining in her career path.

Meanwhile, the spacecraft mission New Horizons is en route to the Kuiper belt. The vehicle will not touch down on Pluto, as Curiosity did on its target planet, but it is scheduled to arrive at that brightest of all KBOs in 2015, for an encounter.

Vijaysree Venkatraman is a Boston-based science journalist.

10.1126/science.caredit.a1200116