Joseph Hooton Taylor

Joseph Hooton Taylor was born in March 1941 in Philadelphia, Pennsylvania. Much of his youth was spent on the family farm in Cinnaminson, New Jersey, in the company of a large group of siblings and cousins, who served as a carefree upbringing on the banks of the Delaware River. Joe’s first forays into scientific investigation were undertaken with his brother, Hal. Together they experimented with ham-radio equipment, an interest that would eventually lead to a profound discovery.

In addition to the know-how acquired in these early technical pursuits, Joe learned valuable lessons about life from his parents, whose Quaker roots in the Philadelphia area go back to the days of William Penn. The traditions of simplicity, tolerance, generosity, and community service that he learned by their example set the stage for a career marked not only by great scientific achievement, but also by contributions to Princeton in the form of teaching and leadership.

Joe attended Moorestown Friends School and then Haverford College, both Quaker institutions about math and science, in his high school and college years he also had a healthy interest and ability in athletics, which captured much of his attention. In his senior year at Haverford, Joe undertook a senior project in radio astronomy that provided an outlet for his practical skills in radio, and tipped him off to the excitement of science. Under the guidance of adviser Thomas Benham, a blind professor who lectured from Braille notes, he constructed a rudimentary radio telescope from two detectors located some distance apart on the edge of the Haverford campus. The apparatus was constructured in the finest physics tradition, using “wire, string, and sealing wax.” Although no new scientific discoveries emerged, Joe was bitten by a bug that he would never shake.

In 1963, having graduated with honors from Haverford with a B.A. in physics, Joe went on to study astronomy at Harvard. Like most graduate students in physics and astronomy, he worked extremely hard at his courses. He pursued his combined interest in radio and astronomy under the supervision of Alan Maxwell, who taught him not just science, but also the scientific craft. As Joe was working on his Ph.D. thesis in Cambridge, Massachusetts. Another graduate student, Jocelyn Bell, and her supervisor Anthony Hewish, from Cambridge University in England, were making the first observations of radio pulsars, celestial objects that would prove crucial to Joe’s future research. Hewish (although not Bell) was awarded the Nobel Prize in Physics in 1974.

Radio pulsars are formed when stats reach the end of their luminous life and collapse into a form of neutron matter (neutron stars) having a mass density about 100 million times that of lead. Like a slowly turning figure skater who pulls in her arms, these massive objects start as gently turning stars before collapsing to the size of a small city spinning at the rate of a kitchen mix master. In some cases, they emit radio waves in beams, which sweep through the sky like the beacon from a light house. Observers in the path of a pulsar’s radio beam detect signals that seem to blink on and off roughly 100 times per second.

Like many radio astronomers of the day, Joe’s interest was piqued by the Bell-Hewish discovery. As a Harvard post-doc, he helped confirm the existence of these peculiar objects, before moving on to a junior faculty position at the University of Massachusetts in 1969. In 1970, Joe enlisted graduate student Russell Hulse to help him improve a technique for systematically seeking out new pulsars. Hulse and Taylor conducted their research using the giant 1000 foot diameter radio telescope at Arecibo in Puerto Rico, a facility subsequently made famous by the movie Contact, starring Jodie Foster. While Joe continued back and forth between Arecibo and Amherst, where he was teaching, Russell renamed at the telescope full time. In September 1974, Russell noticed that one of the pulsar candidates emitted radio bursts that were slightly less regular than those that they had discovered a system comprising two neutron stars orbiting around one another – a so-called binary pulsar.

They went on to deduce that this system would provide a way in which to verify the existence of gravitational radiation, a key prediction of Einstein’s Theory of General Relativity. Through painstaking observations and a series of exquisite calculations. Joe and Russell demonstrated that the time between pulses was very slowly decreasing – just 75 millionths of a second per year – in close agreement with Einstein’s predictions. Experimental tests of general relativity are so rare that Taylor and Hulse were eventually awarded the 1993 Nobel Prize in Physics for their outstanding accomplishment.

By then regarded as one of the nation’s leading radio astronomers. Joe joined Princeton’s physics department in 1980, and in 1986 was named the James S. McDonnell Distinguished University Professor of Physics. At Princeton he and a group of students set out to systematically search for a new class of extremely rapidly rotating pulsars, known as millisecond pulsars. Joe’s team accounted for over half of his first few dozen that were found. He became known as an excellent teacher of undergraduates and a superb mentor to graduate students and other junior colleagues in his group, many of whom have gone on to prolific scientific careers of their own.

In 1992, Joe won the highly prestigious Wolf Prize. With characteristic generosity, he and his wife, Marietta, donated the $100,000 in proceeds to the physics department to establish a graduate fellowship. Joe’s generosity to Princeton came not only form of financial support, but also in the form of service. In 1997 he was named dean of the faculty at Princeton, a post in which he served with distinction until 2003. As dean he worked tirelessly to ensure that Princeton remained strong in areas of existing strength and built strength in areas in need of shoring up. Beyond the Princeton campus, Joe served on numerous review and planning committees, notably a blue ribbon panel to assess the options for extending the life of the extremely successful Hubble Space Telescope, whose future became uncertain as a result of the tragic loss of the Columbia Space Shuttle in 2003.

Joe is universally liked and admitted by his colleagues both within and outside of the physics department. A remark made by Professor Jim Peebles at the press conference held in conjunction the announcement of the Nobel Prize captured a widespread sentiment. Jim said, “One of the best things about this prize is that such a nice person could be involved.”

In recent years, Joe returned to a pursuit that launched his career: ham radio, where he is known simply as “Joe, K1JT.” Using techniques learned in his pulsar research, he has developed a widely distributed program known as WSJT. Among other things, WSJT has put “moon bounce” – communication – long considered one of the biggest technical challenges in amateur radio – within reach of hams unable to afford the large antennas needed prior to its introduction. A Web search for “WSJT” turns up hundreds of sites making mention of Joe’s program (at least as many as “Arecibo”).

The physics department and the University will greatly miss Joe’s leadership in research, teaching, and administrative service, but we are heartened that he intends to play an active role in the department in his retirement years.