It's been some time since I posted. We've had more than 2 months straight months of cloudy nights with a couple of gaps on 3 nights. Two of these produced some lovely NLCs. Here's a shot from Annaghkeen, Headford at about 1:30 am I would guess.
The clouds are the highest in our atmosphere at around 80KMs up in the Mesosphere. The phenomenon is pretty rare and usually only occurs in the summer months at certain latitudes where we have a very prolonged twighlight - the sunlight is reflecting off these ice particles from below.
Click the first image to display a larger version.
or click on play to view the timelapse here: