Professor of Astronomy & Astrophysics, University of California, Santa Cruz
In simplest words, I count atoms and measure the ways that they move. This is the primary product of absorption-line analysis, a backwards approach to performing astrophysics. In short, we use bright background sources (quasars, gamma-ray bursts, etc.) to study gas in the foreground that reveals itself in silhouette. This allow us to study the nature of galaxies and the gas in between them in unprecedented detail.
Half the matter in the universe was missing – we found it hiding in the cosmos
May 29, 2020 14:09 pm UTC| Science
In the late 1990s, cosmologist made a prediction about much ordinary matter there should be in the universe. About 5%, they estimated, should be regular stuff with rest a mixture of dark matter and dark energy. But when...
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