Astronomers using the twin 10-meter Keck telescopes in Hawaii have discovered the most lightweight dwarf galaxy in the Universe - a mere 1,000 stars or so:
The most intriguing aspect of this discovery is that the dwarf galaxy couldn't exist unless dark matter were holding it together. Astronomers believe that a halo of the elusive and yet unseen dark matter is the only way this small collage of stars could be held together.
This discovery helps to gain further understanding of dark matter and how it shapes the Universe. This also may be just the tip of the iceberg as perhaps thousands more of these mini-dawarf galaxies surround our galaxy as well as the billions of other galaxies in the Universe.
Read More About It here: http://keckobservatory.org/news/uci_scientists_size_up_universes_most_lightweight_dwarf_galaxy_with_keck_ob
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