Notre Dame Law Student Finds Rare Wolf-Rayet Star

The galactic nebula NGC 3603, seen by the Hubble telescope, with a cluster of variable Wolf-Rayet stars at its center. NASA/STScI

Colin Littlefield says he has never taken a college physics course. He likes astronomy but plans to make a career as a civil rights lawyer.

So he may be the only law student in America to publish a research paper in The Astronomical Journal. He's discovered a  rare star, a Wolf-Rayet, a hot, giant luminous body that is blasting such large quantities of gas into space that it probably doesn't have long (astronomically speaking) to live.

Littlefield, a first-year student at Notre Dame law school in Indiana, says he has been working nights at the university's observatory, mostly helping other students with research projects or homework. When he was a freshman undergraduate in 2008, he says he took an introductory astronomy course with Prof. Peter Garnavich, and he was hooked.

"I had been an amateur astronomer since middle school, and Prof. Garnavich introduced me to astronomical research, which I found to be thrilling," he wrote in an email.

So there he was studying law by day, helping astronomy students part-time on the side  and doing his own stargazing when the observatory wasn't reserved for other research.

One night last July, he says, he was looking at a variable star in the constellation Cygnus the swan, which appears high in the summer sky over North America. Some Japanese astronomers had put out a request for observations.

He got sidetracked; there was another star nearby, also pulsing in brightness, that wasn't supposed to be there.

"There was no record of this star being a variable star. Its brightness seemed to vary randomly from night to night and even over the course of several hours," he says. With help from Garnavich and Prof. Terrence Rettig, he figured out its chemical composition, something that can be determined from the light it emits, and it was clearly unusual.

"We quickly realized that it was most likely an undiscovered Wolf-Rayet star, albeit one whose appearance is greatly altered by the deleterious effects of interstellar dust," he says.

Wolf-Rayet stars are rare - there are only about 200 known among the Milky Way's 200 billion to 400 billion.  So Littlefield's, which now has the prosaic name WR 142b, merited mention in the scholarly literature.  It is about 4,600 light-years away, though there's uncertainty in the number. It is not visible to the naked eye because of the cosmic dust that surrounds it.

"I generally describe Wolf-Rayet stars as ticking time bombs, as they are destined to explode as supernovae in the astronomically near future," Littlefield says. "Wolf-Rayet stars are in their death throes, and due to their instability, they are ejecting their outer layers into space at prodigious rates."

So what do you do after your first brush with stellar immortality?  You study for finals.  Littlefield is still, after all, a law student.