M85-HCC1
M85-HCC1 is an ultracompact dwarf galaxy with a star density 1,000,000 times that of the solar neighbourhood, lying near the galaxy Messier 85. As of 2015[update], it is the densest galaxy known.
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Wikipedia
M85-HCC1 is an ultracompact dwarf galaxy with a star density 1,000,000 times that of the solar neighbourhood, lying near the galaxy Messier 85. As of 2015[update], it is the densest galaxy known.