astronomers also sometimes think that a poppy-seed cake actually gives a better picture of the expansion of the universe. Before being baked, the poppy seeds are distributed throughout the cake. As the cake rises and expands during baking, each seed in the cake moves away from all the other seeds. The poppy-seed cake also illustrates why astronomers do not think that we can know where our Milky Way galaxy is located within the vast space of the universe itself. If we imagine ourselves sitting on any given poppy seed (or galaxy), all the other seeds (or galaxies) will appear to recede from us
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