In Undefined Fantastic Object, in order to get life pieces, bombs/bomb pieces, to increase your score, you need to catch these UFOs.
These are non-colour-changing UFOs.
This is a colour-changing UFO. You can recognise it by the fact that it blinks. I changes red->blue->green->red
If you are close enough to a blinking UFO, you can make it not to blink and keep it’s colour. But when you go away from it, it will start blinking again.