Model of a black hole, 1970s

This model illustrates the gravitational pull of a black hole—a singularity from which not even light can escape. Hawking used the model to explain his theories to his colleagues at a Royal Society event in the 1970s. Although black holes had been talked about for quite a while by then, Hawking’s theoretical work was both novel and incredibly hard to understand, so a 3D model was necessary to convey his ideas.

Source: Whipple Museum of the History of Science