we have been on this snowy planet before , of course , on and off all of our lives , and our memories cascade in : the world shut down ; sound dampened by the acoustic properties of air trapped inside trillions of snow crystals ; boots , slush , clean smells , bundles and layers of cloth ; the scrape of a snow shovel hitting asphalt ; muffled voices flowing through cold , liquid air ; the comfort , after being out and about on this new planet , of warmth near fires , hot chocolate , brandy , and the miracle of centralized household heat .