Noctilucent cloud , Space Station .夜光雲 ， 太空站

NASA/JSC
Noctilucent cloud captured in Space Station photo - PhotoBlog http://photoblog.msnbc.msn.com/_news/2012/06/25/12403340-noctilucent-cloud-captured-in-space-station-photo?lite

NASA

Martin Koitmäe
Noctilucent cloud - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Noctilucent_cloud
夜光雲 - 维基百科，自由的百科全书 http://zh.wikipedia.org/wiki/%E5%A4%9C%E5%85%89%E4%BA%91