dark matter

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Satellite galaxies can help us understand dark matter’s nature

    From Nature World News, May 20, 2020: Two studies have shown evidence of how a larger satellite galaxy can draw smaller ones into them as they get “trapped” into orbiting the Milky Way. Such an arrangement can inform astronomers and researchers about the nature of the formation of galaxies as well as insights into dark matter and its nature. Fermilab scientist Alex Drlica-Wagner is featured.

    A long-lost type of dark matter may resolve the biggest disagreement in physics

      From Live Science, April 29, 2020: One of the deepest mysteries in physics could be explained by a long-since vanished form of dark matter. Fermilab scientist Dan Hooper is one of the authors of the new result. If an ancient form of dark matter decayed out of existence, that loss would have decreased the mass of the universe, which would have led to less gravity holding the universe together, which would have affected the speed at which the universe expands — helping explain the disagreement between measurements of the universe’s expansion.

      Gamma rays and gravitational lensing provide hints of dark matter

        From Physics World, March 24, 2020: Scientists using the first year of data from the Dark Energy Survey, which is led by Fermilab, establish that there is a correlation between the positions of gravitational lenses — deduced from the stretching of distant galaxies — and gamma-ray photons. A data comparison from gravitational lensing and gamma-ray observations reveals that regions of the sky with greater concentrations of matter emit more gamma rays.