When you walk past the coffeehouse in district 3, there is a big monitor streaming video of Earth. People walking by stop and stare longingly.
They chat amongst themselves, "On Earth, we lived above ground." "Yeah, we could breath the air and drink the water without all these machines."
What is forgotten is that the drinkable water and breathable air were only abundant in ancient times. The industrial ages built on fossil fuel all but destroyed those valuable resources. I teach Earth history, so I can sympathize with their nostalgia.
Still, our underground cities seem to be in harmony with this red planet. Heat from the core warms better than electricity. Sound powers ours machines without exhaust. There is no money, volunteer labor creates everything our society needs.
There is a theory floating around that Earth rejected humanity because of the sound we were making. Our poverty, our greedy, our endless wars were noisy and disturbed the song of the planet. Earth forced us to leave until we grew into a more peaceful species.
That video stream at the coffeehouse is feed by a radio telescope on the Martian surface. Maybe one day, when humanity has evolved, Earth will signal it's time to come back home.
photo: my vinyl of Miles Davis "Bitches Brew" taken with iPhone and its on board camera app.