Rubin Observatory finds two Milky Way companions in 7% of sky survey

· Science

The Vera C. Rubin Observatory has already uncovered two previously unknown companions of the Milky Way using preliminary observations covering just 7% of the night sky, ScienceDaily reported. The discoveries include an extremely faint galaxy 355,000 light-years away and a star cluster hidden behind cosmic dust. Scientists suspect hundreds more such objects may be waiting to be found as the survey continues. The finds come from early data rather than the observatory's full planned survey, suggesting that the final catalog could substantially expand the known population of faint satellites around the Milky Way used in studies of dark matter and galaxy formation.

Why it matters：Faint Milky Way satellites are key test beds for dark-matter models and galaxy formation, and an observatory finding them this fast signals a coming surge in the census astronomers rely on.

Key points

  • One discovery is an extremely faint galaxy 355,000 light-years away.
  • The other is a star cluster concealed by cosmic dust.
  • The findings came from only 7% of the planned sky coverage.

Sources (original reporting)

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