Hubblecast

Light: New test of Einstein’s general relativity (1x110)

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An international team of astronomers using Hubble has made the most precise test of general relativity yet outside our Milky Way. A nearby galaxy acts as a strong gravitational lens, distorting light from a distant galaxy behind it to create an Einstein ring around its centre. By comparing the mass of the lensing galaxy with the curvature of space around it, the astronomers found that gravity on these astronomical length-scales behaves as predicted by general relativity.