Changing particle emission based on how much light is there

Hello! I did a planet with some lights on it:



I want to rotate that planet and the lights should be invisible on the “light” side and visible again on the dark side.

Lights are particles. I did half-sphere, removed some random faces out of it and voila - effect as on picture.
Material is emission.

I am using Cycles engine. Also i got some compositing going on - 2 layers (planet and “atmosphere”) and some glows, blurs etc for glow around the planet.