以表彰他一生對理論天文學的傑出貢獻。
徐遐生(Frank H Shu) 對天文學的貢獻頗多,尤以恆星形成學說見稱。自古以來,人類一直對天上無數閃爍的星星存著好奇。人類想知道星星是什麼?它們在自然界壯觀秩序中有何地位?人類更要了解星星的起源,更想探索星星對我們存在的意義。儘管最近的天文研究有所突破,表明宇宙絕大多數物質成分是暗物質和暗能量,但恆星依然是組成星系的基本單元、是從最遙遠的宇宙到最鄰近世界的可見光波段能量來源、是生命不可缺少及行星棲息所需的各種複雜化學元素的來源。人們必須徹底了解恆星的形成,才可以考究太陽系的形成,並在星系及更大尺度去根查整個體系的誕生。
按照傳統的概念,科學家一直以為恆星是從緻密的星際氣體雲,經過冷卻,受自身引力影響而塌縮形成的。這種模型很理想化,在過去二十多年,受到了觀測發現的挑戰。天文學家利用高精度、大口徑地面望遠鏡,以及哈勃太空望遠鏡等,特別重要的是太空紅外探測器,穿透地球大氣層,直接觀測到恆星誕生的地方,從而理解,恆星產生的環境其實非常複雜,計有:湍動的氣體、無序的磁場以及從新形成的恆星噴出的氣流。
In a career that spans forty-five years, Professor Frank H Shu has spurred fundamental changes in the existing paradigms of three different fields of astrophysics: galactic dynamics, stellar evolution, and the astrophysics of small bodies in the solar system.
Shu’s research career began auspiciously in 1964 with the publication, together with his adviser C C Lin, on the density-wave theory of spiral structure in disk galaxies. Although highly controversial at its inception, this theory has since gathered widespread observational support and computational elaboration. The philosophy that useful theories must be testable has informed all of his subsequent research. Shu has been at the forefront of theoretical developments, particularly with his group’s semi-analytical investigations of the nonlinear, non-ideal theory as applied to galactic shocks in the 1970s and resonantly forced analogues in Saturn’s rings in the 1980s.