@Inky in space, there is simply no "up" or "down" Plasma is made by heating up gas,as it is a 4th state of matter The sky is blue because molecules in the air scatter blue light, otherwise the sky would be red or black While most (if not all) planets are round due to gravity putting it in a condensed sphere,due to it being turned on its axis once every 24 hours, the Earth's equator bulges outwards