Noctilucent clouds:
NLCs [Noctilucent clouds] are, essentially, clouds of frosted meteor smoke. They form when wisps of summertime water vapor rise toward the top of Earth’s atmosphere. Water molecules stick to the microscopic debris of disintegrated meteoroids, assembling themselves into tiny crystals of ice that glow beautifully in sunlight at the edge of space. [Spaceweather.com]
And here’s a perfectly lovely picture from a satellite. I tried to find the original on the AIM site, but that site really needs to be reorganized; this is shamelessly stolen from Spaceweather.com, which claims it found it on AIM.
Credit: NASA/HU/VT/CU LASP
Not all things Earthly look Earthly.
