Description: 在天文学中，亮度是指天体发射的电磁辐射量，或是指我们从天体接收到的光量。

“亮度”一词并不是一个正式的科学术语，但通常用来表示从天体接收到的电磁通量（接收器单位面积在单位时间内接收到的能量，单位：瓦/米²）。“本征亮度”一词通常指天体自身的光度（单位：瓦），而“表面亮度”一词则用于呈延展分布的天体，是指接收器单位面积在单位时间内接收到的天体单位面积的能量（单位：瓦/米²/球面度²，或瓦/米²/弧秒²）。对亮度的这些不同度量，既可以在天体发射的整个电磁波谱上定义，也可以在电磁波谱的特定区域内定义。

出于历史原因，天文学家使用所谓的星等系统来描述一个天体的亮度，这是一个对数系统，给亮度较高的恒星赋予较小的数值。

亮度的变化可以让我们重建物理过程，例如，一颗恒星变大变亮，或者一个较暗的天体从一个较亮的天体前面经过。

Related Terms:

• 电磁辐射
• 光度
• 星等

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".