恒星测光与天体物理的开端

Stellar Photometry and the Beginning of Astrophysics

现代意义上的恒星测光是伴随着宇宙观的转变而产生的。古代天球模型的打破,使人们意识到不同恒星离地球距离并不相同,从而建立起亮度-距离的简单模型。赫歇尔父子对恒星测光做出了开创性的贡献,约翰·赫歇尔制成第一台专门用于天文测光的天文光度计,并通过测光和数据统计认识到恒星亮度不仅与距离有关,而且与恒星内在性质有关。在19世纪前期,天文测光面临"标准烛光"的选取和控制不同观测者对颜色亮度的感知误差两大问题。德国物理学家泽尔纳结合光学与视觉心理学重新设计了天文光度计,一举解决了这两个问题。更为重要的是,经由精确测光,泽尔纳把恒星颜色与亮度联系起来,提出了一套恒星演化理论,成为早期天体物理学理论的代表。

The change of cosmology since the seventeenth century had led to the beginning of stellar photometry.It was realized that there was no solid celestial sphere and the brightness of stars was related to their distance.John Herschel was a pioneer of stellar photometry.He invented the first instrument for stellar photometry.Based on his observational data,he decided that the brightness of stars should not only be related to distance but also related to the inherent nature of stars.In the early 19th century,the stellar photometry faced the problems of how to set up the "standard candle" and how to control the visual illusion about color and brightness.The German physicist Zöllner re-designed the stellar photometer and solved these two problems.More importantly,based on quantitative photometry,Zöllner suggested a relationship between stars’ color and brightness,presenting a first theory of stellar evolution.