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Starbursts in Dwarf Galaxies are a Global Affair


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Bursts of star making in a galaxy have been compared to a Fourth of July fireworks display: They occur at a fast and furious pace, lighting up a region for a short time before winking out. But these fleeting starbursts are only pieces of the story, astronomers say. An analysis of archival images of small, or dwarf, galaxies taken by NASA's Hubble Space Telescope suggests that starbursts, intense regions of star formation, sweep across the whole galaxy and last 100 times longer than astronomers thought. The longer duration may affect how dwarf galaxies change over time, and therefore may shed light on galaxy evolution.

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