Roeland grew up in The Netherlands. After a few years in The Hague, he moved to the suburb of Wassenaar, where he spent most of his childhood. He acquired a love of the exact and abstract already at an early age. His brother was devoted to chess, puzzles, and mathematics and enthusiastically taught his kid brother whatever he would absorb. As a consequence, Roeland participated in his first chess tournament at age seven,with many more to follow. However, despite moderate successes, the interest in chess would not stick. While the chessboard was permanently stored in the closet, a passion for science in general and astronomy in particular has remained to this day. Roeland recalls: "I was never an amateur astronomer. However,I recently came across some old high school notebooks. Amongst the soccer teams and rock stars of the day, I noticed a picture of the Hubble Space Telescope. Apparently, already then I had a good sense of what I wanted to do in life."
After high school, Roeland chose to pursue a double major in astronomy and mathematics at nearby Leiden University, where Lorentz, de Sitter, Oort, and others had established a rich tradition in astronomical research. Although he enjoyed mathematics, it did not draw him in the same way that astronomy did. "Astronomy uses advanced, multi-million-dollar telescopes in exotic places to address questions that humans have pondered for centuries," so he explains. "Mathematics is more abstract and to me just doesn't radiate the same entrepreneurial spirit." Roeland chose to pursue a graduate degree in astronomy. He had been introduced to the field of galaxy dynamics during an undergraduate summer project at Oxford University and chose to make this the topic of his Ph.D.research.
Some galaxies display pronounced activity in their centers, which had long been believed to be due to the presence of supermassive black holes. However, convincing evidence and mass determinations for such black holes from the observed dynamics of stars near galaxy centers was still very scarce. To improve upon this situation, Roeland pioneered new methods for the dynamical modeling of galaxies and for the extraction of kinematical information from galaxy spectra. This work on "two-integral models" and "Gauss-Hermire expansions" built on his background in mathematics. While Roeland considered himself an aspiring theorist, his thesis adviser managed to convince him to try observing as well. Successful observing runs on the William Herschel Telescope on La Palma, combined with Roeland's newly devised methodologies, led to improved constraints on the supermassive black holes in several nearby galaxies. His thesis earned him the Leiden University Kok Prize and a Hubble Fellowship. Detailed comparisons of observation and theory have continued to characterize his research to this day.
After crossing the ocean in 1994, Roeland spent three years at the Institute for Advanced Study in Princeton. During these years he became a frequent user of the Hubble Space Telescope. The Faint Object Spectrograph allowed high spatial resolution spectroscopy of galaxy centers, which yielded some of the best evidence for supermassive black holes. Roeland focused on the stellar motions in M32 and on the gas motions in NGC 7052 and found compelling evidence for supermassive black holes in both galaxies. The axisymmetric, numerical, orbit-superposition models that he constructed have since become the standard approach for the interpretation and analysis of galaxy kinematics. Models of this type have proven to be particularly important for the modeling of data from the Space Telescope Imaging Spectrograph, which have since revolutionized our understanding of the demography of supermassive black holes.
In 1997 Roeland came to the Space Telescope Science Institute as the first Institute Fellow. He is now an Associate Astronomer and also an Adjunct Associate Professor at Johns Hopkins University. He has continued to broaden his research interests, which now include the formation and evolution of all sorts of galaxies (ellipticals, spirals, dwarfs, irregulars, radio galaxies, brightest cluster galaxies, and interacting and merging galaxies), the structure and dynamics of their constituent components (disks, bulges, dark halos, star clusters, and black holes), and the clusters of galaxies in which they often reside. Much of his research centers on data from Hubble, but Roeland is also interested in modeling large ground-based surveys such as CNOC, 2MASS and DENIS. Most recently he has become fascinated with attempts to understand the structure and dynamics of the Large Magellanic Cloud.
For the past few years Roeland was a member of the Institute's Science Policies Division. In this role he worked on the organization of the Hubble peer review process and the editing of documents such as the Hubble Primer and the annual Call for Proposals. He has served the Institute on a variety of committees and has maintained a close interest in the calibration and use of the Hubble instruments. He wrote a target acquisition simulator for the Faint Object Spectrograph, software for "pedestal bias" correction in images with the Near Infrared Camera and Multi-Object Spectrometer, and algorithms for determination of Advanced Camera for Surveys flat fields from repeated observations of star fields.
Roeland is married to Alessandra Aloisi, an astronomer at Johns
Hopkins University. In his spare time he likes to play golf. He loves
movies, various kinds of rock music, and books. Roeland is looking
forward to the challenges provided by his new management
position. "One of the most exciting things about work at the Institute
is the opportunity to work together as a team with people that have
different skills and backgrounds.I feel fortunate to be given the
chance to lead a team of talented people on such an important task."