Astronomers find Candidates for
the missing Dark Matter Objects
predicted by Cosmologists
Rochester, NY – Astronomers are reporting the detection of candidate stars in distant galaxy-sized gas clouds that possibly represent ancient leftovers from the formation period of the Universe. Dr. Eva K. Grebel from the Max Planck Institute in Heidelberg, Germany, Dr. Robert Braun of the Netherlands Foundation for Research in Astronomy, and Prof. W. Butler Burton from Leiden Observatory in the Netherlands are presenting these findings today at the American Astronomical Society meeting in Rochester, NY. Their results are of special interest since they may account for a significant fraction of the missing matter in the Universe and help to understand how galaxies form and evolve.
The view of a compact high-velocity cloud in the light of neutral hydrogen at a wavelength of 21 cm, obtained with the Westerbork Synthesis Radio Telescope by Braun & Burton 2000.
Cosmologists believe that structure in the early Universe formed through condensations of matter along a complex web of connected extended filaments. The more massive condensations in these filaments grew by accreting the smaller subcondensations, a process called hierarchical structure formation. Even today large galaxies continue to grow through accretion of smaller dwarf galaxies not unlike sprawling big cities that incorporate neighboring small towns and hamlets.
While there is plenty of observational evidence for such past and ongoing galaxy merger events, the models predict that we should see ten times more small satellite galaxies than are actually known. Could we have missed such a large number of dim galaxies or are the widely accepted scenarios for the formation and evolution of the Universe wrong? Or did the
Max Planck Institute for Astronomy 
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Press Release
Embargoed For Release: 10:00 a.m. EDT, June 6, 2000

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