1·"To get the noctilucent clouds you need temperatures that are about 20 degrees Kelvin colder than what we see on average up there," Wickwar said.
要获得夜光云，你需要的气温要比我们在那里看到的平均温度冷约20度绝对温度。
2·The recent observations of noctilucent clouds at all kinds of latitudes provide an extra impetus to understand what is going on up there.
最近在各种纬度进行的夜光云观察，提供了了解天上发生着什么的特别动力。
3·The clouds are also called noctilucent, or "night-shining," clouds because they are usually seen at twilight.
这些云也被称为“noctilucent”，也就是“夜光云”，因为他们一般出现在黄昏时分。
4·Polar mesospheric clouds are also known as noctilucent or “night-shining” clouds—a property that is clearly visible in this astronaut photograph.
极地中层云也被称为夜光云层（noctilucent）（就是在夜晚还闪光的云）。 这一特点在这张太空照片上显露无疑。
5·Captured by flickr user, breff 3. A rendering of the noctilucent clouds created from data obtained by Russel’s NASA project, AIM.
利用拉塞尔NASA项目获得的数据绘制的夜光云效果图。