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Astronomy

Gravitational Lensing of Distant Quasars by Foreground Galaxies

Quick fact

Gravitational lensing by a foreground galaxy can split a single quasar's image into multiple copies, sometimes forming an Einstein ring—a glowing circle of light—providing a natural telescope that magnifies the quasar and reveals details about both the galaxy's mass and the quasar's surroundings.

Why this is interesting

Imagine a galaxy acting like a giant magnifying glass, bending light from a quasar billions of light-years away into a cosmic mirage. How can gravity create such perfect illusions?

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Gravitational Lensing of Distant Quasars by Foreground Galaxies

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