This event has finished Took place on: Saturday, 29th Dec 2012
I know not why, only that it is...
...but there is an air-traffic warning that planes should be aware that a laser light show of some sort will take place this evening.
I would presume something to do with The Shard, but it could wll be someone else organising it.
The aircraft notice is from 8pm to 11pm, but the 'event' could be a shorter duration during that window in the calendar.
Update - this may be a rehearsal for New Year's Eve as there is a sepate notice now issued that there will be spotlights from The Shard at midnight NYE.
Cost: Free to watch
Contact and Booking Details
No need to book tickets - just turn up on the day.