cosmic time meaning in English

宇宙时

This relatively short cosmic time frame makes this event a very rare phenomenon
这个在宇宙中相对较短的时间让这个现象非常的稀有。
The deep observations have also traced the waxing and waning of star formation in the universe at large over cosmic time
回溯宇宙年代的深度观测，同时也追踪了整个宇宙恒星形成率的变化。
As incomplete as these four types of evidence are , they indicate that the igm has undergone at least three dramatic changes over the course of cosmic time
上述四类证据尽管不完全，但它们指明了：在宇宙时间的历程上， igm至少已经历三次剧烈的转变。