Science Daily — September 25, 2007
Stars in galaxies are a bit similar to people: during the first phase of their existence they grow rapidly, after which a stellar birth control occurs in most galaxies.
New observations from Dutch astronomer Mariska Kriek with the Gemini Telescope on Hawaii and the Very Large Telescope (VLT) in Chile, have shown that a part of the heavy galaxies already stopped forming stars when the universe was still a toddler, about 3 billion years old. Astronomers suspect that black holes exert an influence on this halt in births.
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