Invisible Universe
The Infinite Monkey Cage
00:00
What Is Dark Matter?
Dark matter is er s you say, it goes back to the 19 thirties and thes observations. It was controversial initially, because you've got to think about the nature of it,. What do we think it might be? Meen, usually twe nt ton nigt, when admit the embarrassing fact that we only understand five per cent of the universe.
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