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future sky

projected movement of our visible sky in an animation covering the next four billion years…..

The Milky Way is seen coming in from the bottom in a face-on and edge-on view. After the interaction, long tidal tails of stars are flung out in open spiral patterns from both galaxies by the strong gravitational tides during the interaction. While separating, the two galaxies develop detailed spiral structure and then fall back for a second collision finally to merge. The mutual annihilation of the two galaxies leads to a big splash showing up as a complicated system of loops and ripples that represent turning points of stellar orbits. The two galaxies finally settle down into a single elliptical galaxy surrounded by remnant debris of their violent interaction.