Types of starburst Classifying the starburst category itself isn't easy since starburst galaxies don't represent a specific type in themselves. Starbursts can occur in disk galaxies , and irregular galaxies often exhibit knots of starburst, often spread throughout the irregular galaxy. However, several different subtypes of starburst are currently under discussion among galactic astronomers: • Blue compact galaxies ( BCG s). These galaxies are often low mass, low metallicity, dust-free objects. Because they are dust-free and contain a large number of hot, young stars, they are often blue in optical and ultraviolet colours. It was initially thought that BCGs were genuinely young galaxies in the process of forming their first generation of stars, thus explaining their low metal content. However old stellar populations have been found in most BCGs and it is thought that efficient mixing may explain the apparent lack of dust and metals. Most BCGs show signs of recent mergers and/or close interactions.
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This note was uploaded on 12/15/2011 for the course AST AST1002 taught by Professor Emilyhoward during the Fall '10 term at Broward College.