Noctilucent clouds and moonn bow Sky scenes from near Silkeborg, Denmark by Anders Falk Jensen. �The night between July the 5th and 6th proved to be a good one for a friend of the atmosphere. As the darkness grew, I noticed the whole sky was filled with NLC's, from south to the north. Truly a grand all sky-display. Then I watched the full moon rising between the clouds to the southeast, in conjunction with Jupiter, wow. Around midnight rain clouds came moving in from the west. The moon was still free from clouds, so I got my camera ready with higher ISO and long exposure. Quite quickly I noticed a weak moon bow on my camera screen, and later I was looking at a complete bow along with the NLC's in the cloud gaps. What a sight, what a night! In the topmost picture, noctilucent clouds (NLCs) throw a delicate skein over the sky. They are Earth�s highest and coldest at some 50-53 miles up in the mesosphere where temperatures can be -160 Celsius.?They might be growing more frequent. Paradoxically, as Earth�s surface and lower atmosphere warms with climate change the mesosphere cools. Above: The precise geometry of a moon bow contrasts with the apparent chaos of NLCs. In this shot some are still visible through gaps in the lower scudding tropospheric clouds. ?Note how in this 13 second exposure the lower clouds blur but the moon bow stays fixed as do the much higher NLCs.

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