Andrew J. Hanson spent his childhood immersed in science. He was born in the midst of the Manhattan Project, where his father was a newly-minted physics PhD, and his Los Alamos birthplace was so secret that his birth certificate says simply "Sandoval County, Rural, New Mexico." After the end of World War II, Andy's father went to the University of Illinois in Urbana, where Andy grew up. Science also extended to Andy's mother's side of the family; his grandfather was a professor of agriculture in the foundational years of that discipline, and all three of his mother's brothers became professors of physics, including Emeritus Professor of Physics Daniel W. Miller of Indiana University. Among the Hanson family's other adventures was a sabbatical year in Torino, Italy, whose voyage home to the US was interrupted on July 26th, 1956, when 12-year-old Andy and his family leapt into the Atlantic Ocean to catch a lifeboat as the Andrea Doria lay foundering behind them. Computers attracted Andy's attention early on; while still a high-school student, he learned to program the Illiac I, worked with computing pioneer Donald Bitzer on the PLATO computer-assisted instruction system, and earned a share of the original PLATO patent. Andy received his BA degree in chemistry and physics from Harvard in 1966, and, being inexorably drawn to physics, earned a PhD in theoretical physics at MIT in 1971. Andy's PhD dissertation concerned an early version of string theory, and that led to his first postdoc at the Institute for Advanced Study in Princeton with legendary mathematical physicist Tullio Regge, which was probably the most influential experience of his career. After a very productive stay in Princeton, Andy continued his postdoctoral career at Cornell, the Stanford Linear Accelerator Center (SLAC), and the Lawrence Berkeley Laboratory. The highlight of this period was his collaboration with another SLAC postdoc, Tohru Eguchi, that led to a remarkable vacuum solution (a so-called instanton) of the Einstein equations, now known as the Eguchi-Hanson metric. In 1980, Hanson led a team with Eguchi and mathematician Peter Gilkey to write an influential book-length review article, "Gravitation, Gauge Theories, and Differential Geometry," detailing the new relationships between physics and mathematics that dominated those times. During this period, Andy became gradually involved in other endeavors, working briefly with Frank Oppenheimer at the Exploratorium Science Museum and then in the Silicon Valley computer industry, ending up spending 10 years at one of the epicenters of Artificial Intelligence, SRI International in Menlo Park, California. There he acquired a basic education in modern computer science, and published papers in image understanding, pattern recognition, and mathematical modeling. His interests eventually shifted, like those of many SRI colleagues, towards computer graphics, and he has remained close to that field since joining the Indiana University Computer Science Department as an Associate Professor in 1989, the first tenure-track position of his 18-year research career. With the help of many inspired and inspiring students, Andy's work at IU has touched on a variety of applications combining graphics and science in the emerging discipline of scientific visualization. In 1990, his first year at IU, he published a paper and an animation (now on YouTube) on "Visualizing Fermat's Last Theorem." Almost a decade later, this work on Fermat surfaces led unexpectedly to another research strand when physicist Brian Greene suggested that there was a close relationship between Hanson's Fermat representations and the Calabi-Yau spaces thought to encode the hidden dimensions of string theory. Subsequently, Andy's images of the Calabi-Yau quintic cross-section appeared in dozens of venues, including Greene's best-selling book, "The Elegant Universe", and the corresponding 2003 PBS NOVA series. A breakfast-table conversation with an old friend in astronomy led to a long-term NASA project on astronomy visualization, resulting in a digital planetarium implementation as well as the animated films "Cosmic Clock" and "Solar Journey." Motivated by the need to interact with four-dimensional space to display his Fermat surfaces and Calabi-Yau space cross-sections, Andy and his students established an extensive framework for visualizing 4D worlds, including knotted spheres, 4D lighting models, and interactive "touchable" 4D objects. An entire branch of this work deals with quaternions (a 4D representation of orientation frames used throughout computer graphics as well as physics), culminating in Andy's 2006 monograph, "Visualizing Quaternions." His most recent work has applied multi-touch interfaces to the fourth dimension, resulting in the iPhone App "4Dice" that allows one to explore the die-like features of a hypercube. If there is one phrase that Andy likes to use to summarize his research career, it is this: "I make pictures of things that no one has ever seen before!" Fortunately for his colleagues at IU, Andy has not spent all of his time lost in four-space. Between 2004 and 2009, he served as chair of the Computer Science Department. This was a crucial, and sometimes difficult, transitional period in the history of the department as we left the College of Arts and Sciences to join the new School of Informatics. Andy proved to be the perfect leader, deftly steering us through the often contentious debates about our future. He will be remembered by all of his colleagues for his good nature, his fairness, and his support for junior faculty. The disciplines of science and mathematics advance today not just through formal analysis but through the insights gained by visualizing the problem. In ways that were unimaginable 25 years ago, it is now possible for scientists to exploit computers to help see and interact with visual representations of extremely abstract problems. Andy is at the forefront of this exciting new field, not only because of his expertise in computer graphics but because of his deep involvement in many of the scientific problems themselves. Given the exciting current developments in theoretical physics, mathematics, and astronomy, there is no way retirement will slow him down. Expect more books, more insights, more interactive software, more animations from this master of visualizing the abstract.