I have no idea

what's brought this on just round the corner from my place.
It's very pretty and I can see it from my front window
(extra from my window at dawn)
But it's not helpful. Mostly.
It's a waste of energy, it's light-pollution - harmful to wildlife
but it's cheery, it lifts the spirit and is probably positive for good mental health, unless of course you are agonising about the waste of energy, the light pollution and the damage to wildlife  .  .  .