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Q & A: Is the world really made of dark matter?

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Most recent answer: 01/04/2010
Q:
is the world really made of dark matter, it doesn't seem like it, I read this book that said the world was made of dark matter
- anonymous
colorado
A:
Dark matter is only one of the several constituents that make up our universe.  Ordinary matter, the kind that you and me and planets and stars are made of , is only 4.6% of the total "stuff".  Dark matter, first proposed by the astronomer Fritz Zwicky in 1934 in order to explain several observed phenomena in galaxies, makes up another 23%.  Dark matter interacts gravitationally with ordinary matter but not with electromagnetic radiation so you can't "see" it.  Since it does interact gravitationally with ordinary matter it affects the formation and evolution of galaxies. We can derive many of its properties from astronomical observations.   The rest of the "stuff", 74%  has been given the StarWars-like name of Dark  Energy.  Currently there are many theories, but few observational proofs, of why or what it is.   It is one of the current  hot topics in astronomy.   Stay tuned.  
See:     for more info or just Google dark matter or dark energy for a whole bunch of interesting articles.

LeeH

(published on 01/04/2010)

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