Ultra-faint galaxies, the subject of Keith Bechtol's feature article in the March 2017 issue of Sky & Telescope, are not easy to find. While Harlow Shapley spotted the Fornax and Sculptor dwarf galaxies in 1938 by examining photographic plates, the darker companions to the Milky Way Galaxy have required modern, statistical methods to suss out. Dominated by dark matter, the smallest of these have only a few hundred stars that we can see, and those must be picked out from a foreground rich with our galaxy's stellar population.
We present here a gallery of some of the larger and more easily spotted ultra-faint galaxies. For more on how these galaxies are shedding light on dark matter, the first stars, and the nature of galaxy evolution, read the March 2017 issue.
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