brightenings
v. (使)变亮;(使)更亮丽多彩;(眼睛)变亮;改善;照亮;(使)高兴;(使)增添乐趣;(使)有希望;放晴(brighten 的现在分词)
例句
These brightenings are known as light echoes.
这些明亮的部分称作光回声。
You can split scores of colorful double stars and spend years following the fadings and brightenings of variable stars.
你可以分解那些五颜六色的双星并且可以花费数年的时间来追踪变星的亮度变化。