If the Earth were to vanish. Like the thought experiment that posits the sun suddenly disappearing to explain the 8 minute delay in the effect on the Earth, so I posit the Earth from the surface down vanishing in equally metaphysical and mysterious circumstances in order to help me to see what the atmosphere would do. So we'd suddenly have a spherical ball of gas with an Earth sized hold in the middle. I understand that the air at ground level has a fair bit of mass about 1.2kg per sq metre, so there's going to be a fair bit of mass in the atmosphere. What would happen and how long might it take. Would it collapse into a solid ball of air, or burst into flame, due to the temperature and the oxygen the collapse, if there was one, would generate, or would it sort of hang there for a very long time doing nothing much at all? Would there be a separation of the layers where the denser lower layer would fall inwards, while the outer lay would float away into space, or would all the layer collapse at the same time seeing as everything falls at the same rate. I think it would collapse but what I'd like to find out, is how dense it would get. But I'm curious to know if it would support itself seeing as it would have a perfect spherical but hollow size like I guess a solid mass would due to there being no difference in pressure on the inside and outside.