IFLSCIENCE - A team of astrophysicists have mapped the “Lyman-Alpha Forest", and provided further supporting evidence that galaxy and galaxy cluster formations are better explained by dark matter than alternative theories.
While observing the universe, astronomers found that galaxies and galaxy clusters don't behave in the way we would expect. In short, stars at the edge of galaxies move so fast (in most, but not all galaxies) that they should be yeeted off into intergalactic space given the amount of visible mass we can see in those galaxies.
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In the new study, astrophysicists from the University of California, Riverside, used the “Lyman-Alpha Forest" to attempt to indirectly map dark matter. Essentially, they looked at light from distant sources and mapped drops in light along the hydrogen wavelength. These drops in light correspond to matter the light has encountered along the way.
“It’s somewhat like shadow puppetry, where we guess the character placed between the light and the screen based on its silhouette,” Simeon Bird, associate professor of physics and astronomy and lead author of the study, said in a statement.