A Dwarf Galaxy That's Almost All Dark Matter

By Brian Koberlein - November 02, 2023 12:51 PM UTC | Extragalactic
Thanks to new techniques, astronomers are mapping the Universe with more precision, finding galaxies with more and less dark matter. Now astronomers think they've found one that's almost all dark matter with few stars. Dubbed "Nube", the galaxy contains about the same mass as the Large Magellanic Cloud, measuring 22,000 light-years across, with almost no stars inside it. This is the most massive and extended "Almost Dark Galaxy" astronomers have ever found.
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Satellites Make up to 80,000 Flashing Glints Per Hour. It's a Big Problem for Astronomers

By Brian Koberlein - October 31, 2023 12:05 PM UTC | Observing
Telescopes searching for brief flashes like supernovae and asteroids have to contend with a rising number of glints from satellites. These glints can last for a fraction of a second, but they're bright enough to be recorded as a starlike object in the field of view of a survey like the Vera Rubin Observatory. In a new study, astronomers identified tens of thousands of these glints captured by a survey telescope, and there could be 80,000/hour happening across the sky.
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