Astronomers have observered a phenomenon known as gravitational microlensing in stars for the first time. Predicted by Einstein as part of his theory of general relativity, this could help measure the mass of distant stars using gravitational deflection.
According to Einstein’s general relativity theory, spacetime bends or gets distorted when it crosses a massive object due to its gravity. In the same manner, Einstein theorized that such a distortion also happens to light from a distant star when it passes another star along a line of sight from Earth — like a near stellar eclipse, so to speak. In this case, gravity should act as a magnifying lens by brightening and bending the light from the distant star, warping its apparent position.
Einstein, however, wasn’t particularly confident about ever seeing such this gravitational deflection of starlight. In an article published in Science in 1936, he said that because stars are so distant from one another “there is no hope of observing this phenomenon directly.” An international team of researchers, however, have just proven Einstein wrong — but also right — by seeing a type of gravitational microlensing from a star other than the Sun.