Some Astronomers Searching for What the Mysterious "Dark Matter" Might

question 9

Multiple Choice

Some astronomers searching for what the mysterious "dark matter" might be made of have pinned their hopes on MACHO's (MAssive Compact Halo Objects) . What do they think these MACHO's are?

• A) huge concentrations of antimatter, outside of galaxies
• B) vast clouds of neutrinos, emitted by ancient supernovae
• C) black holes, brown dwarfs, and white dwarfs in the regions outside the main disk of our Galaxy
• D) "cannibal galaxies" that have swallowed smaller galaxy neighbors until they have grown very large
• E) large groups of college football players who have flunked astronomy, and now hang around the outskirts of town, just showing off their muscles

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