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An impossibly small clump of stars is orbiting the Milky Way without breaking apart, which could mean it is the least massive galaxy ever spotted. Although it only contains about 57 stars, it may be chock-full of dark matter.
The strange cluster, called Ursa Major III/UNIONS 1, orbits our galaxy about 33,000 light years from the solar system. It is the smallest and faintest satellite of the Milky Way…