It'S behind you

  title={It'S behind you},
  author={Anil Ananthaswamy},
Ananthaswamy examines the existence of dark matter. The strongest evidence for dark matters existence comes from observations of how galaxies rotate and how clusters of galaxies behave. If the only matter in the universe were normal matter, then galaxies and clusters would have long since come apart--there wouldn't be enough mass, and therefore gravity, to hold them together. And there must be a lot of the dark stuff: the best estimates suggest that it accounts for 85 to 90 per cent of the… CONTINUE READING