Light blue concidered the color of thinking. Our mind wanders the imagined endless air above us in search for thoughts and memories and spirit, things we know are there in our memory, we even cast a glancing eye up to the sky in search. Colors have profound emotional meaning. The color of the sky is the least loaded, lightest of the colors, fading into white, into nothingness openness positive and optimism. Dark blue always fades into an uncertant unknowing black.
This why the name.