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Astronomy

Gravitational Lensing and Its Uses

Quick fact

Gravitational lensing can create multiple images of the same distant galaxy, arranged in arcs or even a complete circle called an Einstein ring — a cosmic 'hall of mirrors' predicted by Einstein's theory.

Why this is interesting

We know gravity bends the path of a ball or a planet, but did you know it can also bend light itself — creating cosmic magnifying glasses that let us see the most distant parts of the universe?