Using NASA and ESA’s Hubble Space Telescope, EPFL scientists have identified several rare cases of galaxies that contain supermassive black holes acting as gravitational lenses. Two years ago, scientists in EPFL’s Laboratory of Astrophysics (LASTRO) discovered a quasar, a galaxy with a black hole at its center, that functioned as a gravitational lens, a kind of cosmic magnifying glass. They have since found several more situations like this and are able to measure the mass of quasar based on the amount the light is bent in the gravitational lensing of the background galaxy.
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