Around 12:00 am, few faint filaments of the night shining clouds (Noctilucent clouds / NLC) appeared in the sky towards the direction of setting sun on 2017 July 18. The sun had already an inclination of approximately -12 degrees marking the nautical dusk and astronomical dawn. As the clouds slowly swept towards the darker direction and disappeared in the next 1 and half hours, another band of brilliant white NLCs appeared from the horizon in the direction of the brightest sky (the second half of the video). By this time, the sun was beyond -13 degree inclination clearly marking the astronomical twilight. The time-lapse is created from 1479 individual snaps; the shutter speed is adjusted by a couple of seconds more a few times during this capture sequence to compensate the darkening sky. In the last few 100 clicks, I had to turn the camera a little bit towards the North East to frame the NLCs that appeared in the distant horizon. The big dipper can be seen sweeping towards the right from the top left corner.