Tribute to Sun Kwok

Sun Kwok was bom in Hong Kong in 1949. He did all his early schooling in Hong Kong and went to the same high school, Pui Ching Middle School, as I did but he was more than a decade later. There are two Education Systems in Hong Kong; the Chinese Language Schools and English Language School. Pui Ching was started by Christian missionaries in China and has a long history of providing quality education. Pui Ching is a Chinese Language School, and during colonial times, school entrance was difficult for students as we were not eligible to apply for admission to the University of Hong Kong, nor were we able to join the civil service. In spite of these handicaps, the school still managed to produce many excellent academics, including one Nobel Prize winner in physics and one Field's medalist in mathematics. Most of its graduates who sought further education went to the U.S. Or Canada as Sun Kwok did. Sun graduated from McMaster University and then went to the University of Minnesota for graduate studies. In the early 1970s, the University of Minnesota had just built one of the world's first infrared bolometers and the astronomers there (Nick Woolf and Ed Ney) were able to make some of the first infrared observations in the mid-infrared region. Through these observations, circumstellar dust was discovered, leading to the realization the evolved stars are losing mass. Sun wrote his PhD thesis on the mass loss mechanism of red giant stars, proposing that the stellar winds are driven by the mechanism of radiation pressure on grains. His 1975 paper is still widely cited to this date. In the same thesis, he showed that OH maser emission is a manifestation of the mass loss process and OH/IR stars are the most heavily mass-losing stars known. He went back to Canada for postdoctoral studies, first at UBC and then at York University. While at York, he applied his knowledge of mass loss to the problem of formation of planetary nebulae, leading to now well-established interacting winds theory which revolutionized our understanding of the evolution of planetary nebulae. After he joined the University of Calgary, he collaborated with Bruce Hrivnak to discover many proto-planetary nebulae, the then missing link between asymptotic giant branch and planetary nebulae. Together with his former graduate student Kevin Volk, he analyzed the spectra obtained from the Low Resolution Spectrometer of the IRAS satellite and discovered the mysterious 21 micron emission feature, a feature that is still unidentified to this date. Through his work on millimeter-wave and infrared spectroscopy, Sun promoted the idea that evolved stars are prolific molecular factories. In addition to molecules and minerals, he suggested that evolved stars are also producing complex organics. His paper in Nature in 2004 demonstrated that organic synthesis in the late stages of stellar evolution can contaminate the chemical content of the Galaxy and can even affect the chemical composition of the primordial solar system. In addition to publishing in scientific journals, Sun has also written numerous articles in popular science magazines and given public talks to general audience all over the world. His two popular science books Cosmic Butterflies (Cambridge 2001) and Stardust: the cosmic seeds of life (Springer 2013) are extremely successful in the amateur astronomy communities. Sun is a dedicated teacher. He invested a great deal of efforts in his teaching. From the notes he developed over 20 years, he wrote the textbook Physics and Chemistry of the Interstellar Medium (University Science Books 2006). This book is now widely used all over the world, including leading universities such as Caltech. Sun has also been active in international service, having served as President of the IAU Working Group of Planetary Nebulae, President of IAU Commission 34 Interstellar Matter, and is the current President of IAU Commission F3 Astrobiology. Sun returned to Hong Kong in 2006 to take up the position as the first appointed Dean of Science at the University of Hong Kong. As soon as he arrived, he began to reform the science curriculum at HKU, beginning with the introduction of a flexible major/minor system, Faculty common admission, experiential learning requirements, an academic advising system, creation of the interdisciplinary major Environmental Science, introduction of academic induction, undergraduate summer research fellowship and overseas research fellowship, and science service courses for engineering and medicine students. The most significant was his creation of a one-year core sequence of new science foundation courses, which introduced new ways of teaching mathematics and science at the undergraduate level. He is also committed to the internationalization of academic staff, having brought in new hires from many different countries and greatly raising the quality of the staff as a result. In spite of his heavy administration duties, Sun continues to teach every year. He designed and taught the course Our Place in the Universe as part of the Common Core of HKU. The course discusses the impact of 5000 year of astronomical development on society, religion and society. In 2016, Sun Kwok will have completed his 10-year tenure as Dean. I am glad to have the opportunity to dedicate the 11th Pacific Rim Conference on Stellar Astrophysics to celebrate the academic career of Sun Kwok. Many of us present here are well familiar with the influence Sun has effected over his career on the physics and chemistry of the late stages of evolution. I am very glad to see that so many experts in this field are gathered here in Hong Kong and I wish everyone a very successful and productive conference. I also wish Sun will continue his productive scientific research after he no longer has the administrative burdens and we look forward to more exciting science results from Sun in the years to come.