They may be monsters of the universe, but elliptical galaxies can start life in the same way as snowf lakes. It has long been assumed that these most massive of galaxies form when two smaller spiral-shaped galaxies collide. But there is an alternative theory in which a cloud of gas collapses in on itself to form a dense core of stars which then grows larger by assimilating smaller galaxies over time. This is similar to how ice crystals build up around a microscopic dust grain as it falls to Earth, forming a snowf lake.
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